Couchbase Server Release Notes for 2.5.2 GA¶

Couchbase Server 2.5.2 (December 2014) is a maintenance release for Couchbase Server 2.5 that includes bug fixes.

Fixed or resolved issues in 2.5.2¶

Server operations

• MB-12451: If the socket connection closes during large data reads, the document data leaks.
• MB-12178: Race condition can occur when notifying memcached of checkpoint persistence and memcached worker thread tries to add a new checkpoint.
• MB-11611: memcached.logs can grow large after the node failure and bucket flush.
• MB-11137: When a write commit failure occurs and an alert email is sent, a crash occurs.
• MB-10921: Fixed file descriptor leak in views with reduce function

Cluster operations

• MB-12241: A memory leak can occur when a vBucket is deleted and there are items to fetch in the background queue.
• MB-12156: Race condition with time check when changing data path may lead to deletion of all vBuckets after adding node to cluster.
• MB-11825: Rebalance could fail if node compatibility check times out.
• MB-11037: High cluster replication latency due to pausing and resuming the TAP connection for new mutations and high SET workload.
• MB-10406: If an item on a replica vBucket is locked, replication or rebalance fails.

XDCR

• MB-12706: In an XDCR environment, when an add-delete-add operation is performed, the second add operation fails when performed on temporary items.
• MB-12238: An infinite timeout on outgoing xmem request might lead to XDCR hanging when there are network or NAT issues.
• MB-11411: With XDCR, warmup with an access log always sets the loaded document’s rev-id to 1.
• MB-10437: XDCR replication rate drops with a light write workload on the source cluster.

Known issues in 2.5.2¶

N/A

Couchbase Server Release Notes for 2.5.1 GA¶

Couchbase Server 2.5.1 (April 2014) is a maintenance release for Couchbase Server 2.5 that includes bug fixes.

Fixed or resolved issues in 2.5.1¶

Server operations

• MB-8039: Failover is slow when nodes do not respond.
• MB-9457: Pass +swt low to erlang
• MB-10051: Need a way to modify % metadata warning
• MB-10227: Scheduled compaction crashing on GET operation.

XDCR

• MB-10057: Rebalance should reset xdcr checkpoints
• MB-10059: Replica vbucket simply ignores rev_seq values of new items from the active bucket.
• MB-10127: Several Erlang crashes on source XDCR nodes: Cannot allocate 21240272840 bytes of memory (of type “heap”)

Command-line tool

• MB-10102: Need a packaged tool or couch_dbdump option to extract _local docs out of couchstore file
• MB-10103: Couch_dbdump –byid option is not working
• MB-10116: cbcollectinfo may leak private key
• MB-10171: Need at least hack-ful way to include _local/ docs of master vbucket into cbcollectinfos

Cluster operations

• MB-10114: An item should not be removed from cache when SET operation for that item fails due to ENGINE_ENGINE_E2BIG or ENGINE_ENOMEM
• MB-10277: TOUCH command for a non-resident item causes a segmentation fault when an item’s expiration time remains in the same

Installation and upgrade

• MB-10220: vBuckets shuffle in online upgrade from 2.2.0-837 to 2.5.0-1059 in 1 replica bucket
• MB-10515 Online upgrade failed from 2.5.0-1059 -> 2.5.1-1073 as 2.5.1-1073 node doesn’t appear in orchestrator after adding to the cluster.

Known issues in 2.5.1¶

XDCR may not replicate some mutations:

• MB-11411: Warmup with an access log always sets the loaded document’s rev-id to 1.

Symptoms:

Users of XDCR may notice that the replica bucket has old revisions of documents and can also contain documents which have been deleted in the source bucket. This symptom typically occurs following a restart of a Couchbase Server node.

Under uni-directional XDCR replication, resetting of revision IDs may cause mutations to be missed at the destination cluster for a period of time.

:Under bi-directional XDCR, resetting of revisions IDs may cause updates to be overwritten by out-of-date data for a period of time while XDCR re-synchronizes data in both directions.

Recommendations:

Contact Couchbase Support (support@couchbase.com) to obtain the hotfix and repair XDCR. If you are running Couchbase Server versions 2.0, 2.0.1, 2.1 or 2.2, upgrade to Couchbase Server 2.5.1 and apply the hotfix.

To repair uni-directional XDCR: stop XDCR, delete and recreate the destination bucket, and start XDCR.

To repair bi-directional XDCR: contact Couchbase support for assistance.

Couchbase Server Release Notes for 2.5 GA¶

Couchbase Server 2.5 (February 2014) is a minor release following Couchbase Server 2.2. This includes some important new features and bug fixes.

Deprecated settings in 2.5¶

The following REST API XDCR internal settings are deprecated and unavailable:

• xmemWorker
• enablePipelineOps
• localConflictResolution

Enhancements in 2.5¶

Couchbase Server 2.5 includes the following new features and enhancement:

• Rack Awareness (Enterprise Edition only)
• XDCR data security (Enterprise Edition only)
• Optimized connection management

Rack Awareness feature¶

The Rack Awareness feature allows logical groupings of servers on a cluster where each server group physically belongs to a rack or availability zone. This feature provides the ability to specify that active and corresponding replica partitions be created on servers that are part of a separate rack or zone. This increases reliability and availability in case entire racks or zones become unavailable.

See the following for more information about Rack Awareness:

• For concept details on Rack Awareness and Server Groups, see Rack Awareness.
• For administrative tasks on managing Rack Awareness, see Managing Rack Awareness.
• For command line interface information on managing server groups, see the couchbase-cli and Managing Rack Awareness CLI.
• For REST API information on managing server groups, see the Rack Awareness REST API.

XDCR data encryption feature¶

The cross data center (XDCR) data security feature provides secure cross data center replication using Secure Socket Layer (SSL) encryption. The data replicated between clusters can be SSL-encrypted in both uni and bi-directional.

With the XDCR data security feature, the XDCR traffic can be secured by selecting the XDCR encryption option and providing the remote cluster’s certificate.

See the following for more information about XDCR data encryption:

• For concept details on XDCR and XDCR data encryption, see Cross Datacenter Replication and XDCR data encryption.
• For administrative tasks on managing XDCR data encryption, see
  Managing XDCR and Managing XDCR data encryption.
• For command line interface information on managing XDCR and XDCR data encryption, see the couchbase-cli, Managing XDCR CLI, and Managing XDCR data encryption CLI.
• For REST API information on managing XDCR and XDCR data encryption, see the XDCR REST API and Managing XDCR data encryption REST API.

Optimized connection management¶

In releases prior to Couchbase Server 2.5, a developer, via a client library of their choice, randomly selects a host from which to request an initial topology configuration. Any future changes to the cluster map following the initial bootstrap are based on the NOT_MY_VBUCKET response from the server. This connection is made to port 8091 and is based on an HTTP connection.

Starting with Couchbase Server 2.5, client libraries may instead query a cluster for initial topology configuration for a bucket from one of the nodes in the cluster. This is similar to prior releases. However, this information is transmitted via the memcached protocol on port 11210 (rather than via persistent HTTP connections to port 8091). This significantly improves connection scaling capabilities.

Optimized connection management is backward compatible. Old client libraries can connect to Couchbase Server 2.5, and updated client libraries can connect to Couchbase Server 2.5 and earlier.

For more information, see Using a smart (vBucket aware) client in Deployment strategies.

Upgrade notes for 2.5¶

When upgrading to Couchbase Server 2.5, if the cluster has more than one (1) replica configured during swap rebalance, some vBuckets are re-distributed across the cluster.

With XDCR data encryption, the following ports are reserved:

Port	Description
11214	Incoming SSL Proxy
11215	Internal Outgoing SSL Proxy
18091	Internal REST HTTPS for SSL
18092	Internal CAPI HTTPS for SSL

Fixed or resolved issues in 2.5¶

MB-10058: With xmem implementation, mutations may be “dropped” if there are less than 10 memcached errors in the set-meta batch.

MB-9953: For XDCR, mutations are not replicating to the destination cluster.

MB-9938: In a DGM scenario, memcached disconnects when doing disk fetches.

MB-9926: In XDCR, xmem replication fails to send documents for which get-meta requests failed.

MB-9864: Corrupted messages are logged in the ep_warmup_access_log access log file.

MB-9800: Partition 910 not in active or passive set error during rebalance.

MB-9745: XDCR recovery time is slow when an error is encountered.

MB-9693: Remote memcached and ep_engine returns ENOENT incorrectly.

MB-9677: A memory leak in the client-side moxi occurs during rebalance.

MB-9663: With XDCR, vBuckets are slow to replicate.

MB-9549: A memory leak occurs when the TTL is updated for a non-resident item.

MB-9451: Running cbcollect-info causes nodes to automatically failover.

MB-9361: On Windows, rebalance fails with a `Cannot allocate 18380923 bytes of memory (of type \“binary\”)‘ error message.

MB-9209: With XDCR, beam memory usage over time increases for the source cluster.

MB-9147: lseek can return 0, so only assert if lseek < 0.

MB-8724: Moxi 1.8.1 leaks memory and crashes via the Linux OOM killer.

Known issues in 2.5¶

To browse or submit new issues, see http://www.couchbase.com/issues/browse/MB-xxxx

MB-9992: vBucket issue

Under certain circumstances, the ep-engine flush API may not completely free up all memory in a bucket. This API has not been supported in the past few releases. Note: This does not affect the REST API flush command.

Workaround: Delete and recreate the bucket.

MB-9612: On the destination cluster, XDCR spams the cluster management error logs with tmp errors.

MB-9858: vBucket issue

A high percentage of vBucket memory quota used on a vBucket causes rebalance to fail because the backfill task for the vBucket takeover is temporarily suspended due to high memory usage.

MB-10049: CLI syntax issue

The couchbase-cli xdcr-setup --xdcr-cluster-name option is misspelled in the CLI help. --xdcr-cluster-name is correct. --xdcr-clucter-name is incorrect.

MB-10005: XDCR data encryption issue

Upgrade to Couchbase 2.5 Enterprise Edition succeeds when reserved ports for XDCR data encryption are used by buckets.

MB-10000: XDCR and CLI issue

The couchbase-cli xdcr-setup allows --xdcr-cluster-name as an optional option while Web Console has this field as mandatory.

MB-10057: With XDCR, Rebalance does not reset XDCR checkpoints. In some cases, XDCR checkpointing may reuse old and stale checkpoints which caused stuck replication.

MB-10059: Replica vBuckets ignore rev_seq values of new items from the active vBucket. Instead, new rev_seq values are generated for those new item. With XDCR, an inconsistent state may occur.

Couchbase Server Release Notes for 2.2 GA¶

These releases apply to the previous Couchbase 2.2 build 821 and current Couchbase 2.2 build 837.

Release 2.2.0 - build 837¶

These release notes are for the current Couchbase build 2.2.0-837. The release notes for Couchbase build 2.2.0-821 also apply. In addition, the following issues were fixed:

Fixes in 2.2.0-837

MB-9073: On recreate XDCR replication, the settings default to the last created replication mode; it should default to “xmem”.

MB-9140: The “Contact” link is invalid on the initial setup page.

MB-9209: With XDCR, beam memory usage over time increases for the source cluster.

MB-9422: For certain vBucket maps, cbrecovery fails to create recovery map and crashes.

MB-9467: Enforce some limits during view indexing.

Known Issue in 2.2.0-837

MB-9612: On the destination cluster, XDCR spams the cluster management error logs with tmp errors.

MB-10057: With XDCR, Rebalance does not reset XDCR checkpoints. In some cases, XDCR checkpointing may reuse old and stale checkpoints which caused stuck replication.

MB-10059: Replica vBuckets ignore rev_seq values of new items from the active vBucket. Instead, new rev_seq values are generated for those new item. With XDCR, an inconsistent state may occur.

Release 2.2.0 - build 821¶

These release notes are for the previous build 2.2.0-821.

Couchbase Server 2.2 (September 2013) is our minor update release for Couchbase Server 2.0. This includes some major enhancements, new features and important bug fixes. Also with this we have extended our platform support for Windows 2012 and provide separate packages for Ubuntu 12.04 and CentOS 6.

To browse or submit new issues, see Couchbase Server Issues Tracker.

The major enhancements available in Couchbase Server 2.2 include:

• XDCR performance optimization through new mode of replication which utilizes highly efficient memcached protocol on the destination cluster for replicating changes. See Behavior and Limitations.
• Disk storage optimization through new metadata purge settings for permanently purge metadata on deleted items. See Disk Storage.
• New read-only admin user to Couchbase Server. This user will have access to Couchbase Server and its Admin UI, tools and REST APIs but only in read-only mode. See Account Management.
• New addition to our toolset CBRecovery tool that provides additional durability from remote cluster. See CLI Tools.

Additional enhancements in 2.2 include:

• Instructions for non-root, non-sudo installation and running of Couchbase Server and its tools. See Installing Couchbase Server.
• CRAM-MD5 support for SASL authentication on Couchbase Server. See Providing SASL Authentication. See Couchbase Developer Guide 2.2, Providing SASL Authentication
• Ability to reset password for Administrator using the CLI command. See cbreset_password Tool.

Fixes in 2.2

• Command-line Tools

  • In past versions of Couchbase Server, cbbackup would continue past 100% progress. This is due to a a bug in the cbbackup progress indicator and tool behavior. In the past, cbtransfer only accounted for items in RAM in the backup estimate, but would also backup deleted items as well as items read from disk into memory. This resulted in greater than 100% progress being displayed. These issues have been fixed.

    Issues : MB-8692

• Indexing and Querying

  • In the past you had to delete an XDCR replication and recreate it if you wanted to change any XDCR internal settings. This includes: xdcr_optimistic_replication_threshold, xdcr_worker_batch_size, xdcr_connection_timeout, xdcr_num_worker_process, xdcr_num_http_connections, and xdcr_num_retries_per_request. You can now change these settings and they will immediately apply to the existing XDCR replication. For more information, see Changing Internal XDCR Settings.

    Issues : MB-8422

• Cross Datacenter Replication (XDCR)

  • If you used a custom data path then performed a server uninstall and upgraded, older XDCR replication files were left intact. This resulted in Couchbase Server crashes and incorrect information in Web Console. This has been fixed.

    Issues : MB-8460

  • Non-UTF-8 encoded keys will not be replicated to destination clusters via XDCR by design. See Behavior and Limitations.

    Issues : MB-8427

• Performance

  • Users experienced higher latency rates when they performed observe for replicated data. We have now fixed the issue.
    Latency is now at least 5 times faster for this use case for Couchbase Server 2.2.

    Issues : MB-8453

  • Users may experience segmentation faults if a cluster is under heavy stress. For example if your cluster has a very high disk write queue such as 2 million items per node, several XDCR replications, plus thousands of writes per second, the disks will drain slower.

    With a similar workload and limited hardware, synchronization delays in I/O may occur resulting in a segmentation fault. This may result in data-loss. We therefore recommend you have adequate cluster capacity and monitor operations per second on your cluster.

    Issues : MB-9098

Known Issues in 2.2

• External IP Addresses and EC2

  • In the past you were able to add a node to a cluster in EC2 with an external IP address. If this address did not resolve, any error was ignored and the server used a local IP address for the node. The server now
    displays this error, “54.241.121.223”: eaddrnotavail". If you using Couchbase on Amazon EC2 we recommend you use Amazon-generated hostnames which then will automatically resolve to either the internal or external address. For more information, see Handling Changes in IP Addresses

    Issues : MB-8981

• XDCR and Tombstone Purging

  • If you are using XDCR, Couchbase Server 2.2 introduces new functionality known as tombstone purging. This functionality runs as part of auto-compaction. If you set the purge interval to a fairly low number, such as less than one day, you may experience significant mismatch in data replicated from a source to destination cluster. For more information about tombstone purging see Enabling Auto-Compaction.

    Issues : MB-9019

• XDCR and Elastic Search

  • If you are using Elastic Search with Couchbase Server 2.2, you must use the REST protocol for XDCR replication to Elastic Search. Otherwise Elastic Search will fail and return the error code 500. For more information about XDCR protocols, see XDCR Behavior and Limitations.

    Issues : MB-9049

• Installation and Upgrade

  • For Mac OSX, if you move the server after it is installed and configured, it will fail. If you must move a configured server on this platform, you should first stop the server, delete the config.dat file found at *install_directory*/var/lib/couchbase/config, start the server and configure it once again.

    Issues : MB-8712

  • If you upgrade to 2.1.1 or later from 2.1.0 or earlier the server may not automatically start after you reboot the machine. You may need to check your firewall settings and flush any iptables before the server will automatically restart after upgrade.

    Issues : MB-8962

  • If you upgrade an Ubuntu system from 1.81 to 2.2.0, the node referenced by the host name is reset during the upgrade.

    Workaround: Before upgrading, make sure you put the host name under /opt/couchbase/var/lib/couchbase/ip so the installer can back it up as ip.debsave and determine the host name after the upgrade.

    Issues: MB-8932, MB-9109

• Database Operations

  • Any non-UTF-8 characters are not filtered or logged by Couchbase Server. Future releases will address this issue.

    Issues : MB-8427

  • If you continuously perform numerous appends to a document, it may lead to memory fragmentation and overuse. This is due to an underlying issue of inefficient memory allocation and deallocation with third party software tcmalloc.

    Issues : MB-7887

• Cluster Operations

  • The detailed rebalance report in Couchbase Web Console display numbers for Total number of keys to be transferred and Estimated number of keys transferred when you rebalance empty data buckets. We incorrectly show the number of internal server messages that will be transferred and have been transferred, instead of only documents in a data bucket. This will be fixed in future releases. For more information about detailed rebalance information, see Monitoring a Rebalance.

    Issues : MB-8654

  • A cluster rebalance may exit and produce the error {not_all_nodes_are_ready_yet} if you perform the rebalance right after failing over a node in the cluster. You may need to wait 60 seconds after the node failover before you attempt the cluster rebalance.

    This is because the failover REST API is a synchronous operation with a timeout. If it fails to complete the failover process by the timeout, the operation internally switches into a asynchronous operation. It will immediately return and re-attempt failover in the background which will cause rebalance to fail since the failover operation is still running.

  Issues : MB-7168

• Command-line Tools

  • If you use cbbackup, cbrestore, or cbtransfer you should perform the backup, restore, or transfer from a node in your Couchbase cluster. These three tools will not transfer data from external IP addresses; they will function with IP addresses from an internal Couchbase cluster node list. See cbbackup Tool.

    Issues : MB-8459

  • Several incidents have been reported that after using flush on nodes, Couchbase Server returns TMPFAIL even after a successful flush. This may occur for Couchbase Server 2.0 and above.

  Issues : MB-7160

  • For Mac OSX there is a bug in cbcollect_info and the tool will not include system log files, syslog.tar.gz. This will be fixed in future releases.

  Issues : MB-8777

Couchbase Server Release Notes for 2.1.1 GA¶

Couchbase Server 2.1.1 (July 2013) is first maintenance release for Couchbase Server 2.1. This release includes some major bug fixes and enhancements:

New Edition in 2.1.1

The Enterprise Edition of Couchbase Server is now available on Mac OSX. See Couchbase, Downloads.

Fixes in 2.1.1

• Database Operations

  • There was an underlying Windows Management Instrumentation issue in wmi_port.cpp which caused memory leaks. This has been fixed.

    Issues : MB-8674

  • The 2.1 version of the server exposes fewer server stats than it did in earlier versions. The five stats that have been removed are key_data_age, key_last_modification_time, paged_out _time, ep_too_young and ep_too_old.

    Issues : MB-8539

• Cluster Operations

  • The rebalance speed for small datasets has been significantly improved. This includes time to rebalance empty buckets and buckets containing tens of thousands of items.

    Issues : MB-8521

  • In Couchbase 2.1.0 if you tried to assign a hostname to a node when you join the node to a cluster, it will be reset. The hostname will not be saved for the node and will not be used by the cluster to identify the node. This has been fixed. For more information about managing hostnames, see Using Hostnames with Couchbase Server.

    Issues : MB-8545

Known Issues in 2.1.1

• If you upgrade to 2.1.1 or later from 2.1.0 or earlier the server may not automatically start after you reboot the machine. You may need to check your firewall settings and flush any iptables before the server will automatically restart after upgrade.

  Issues : MB-8962

Couchbase Server Release Notes for 2.1.0 GA¶

Couchbase Server 2.1.0 (June 2013) is the first minor release for Couchbase Server 2.0 and includes several optimizations, new features and important bug fixes.

The major enhancements available in Couchbase Server 2.1.0 include:

• Improved disk read and write performance with new multi-threaded persistence engine. With the newly designed persistence engine, users can configure the multiple read-write workers on a per Bucket basis. See Disk Storage.

• Optimistic Replication mode for XDCR to optimistically replicate mutations to the target cluster. More information can be found here: ‘Optimistic Replication’ in XDCR

• More XDCR Statistics to monitor performance and behavior of XDCR. See Monitoring Outgoing XDCR.

• Support for hostnames when setting up Couchbase Server. See Using Hostnames with Couchbase Server.

• Rebalance progress indicator to provide more visibility into rebalance operation. See Monitoring a Rebalance.

• Ability to generate a health report with cbhealthchecker, now included as part of the Couchbase Server install. See cbhealthchecker Tool.

• Importing and exporting of CSV files with Couchbase using cbtransfer. See cbtransfer Tool.

• Server-side replica-read API. Couchbase Developer Guide, Replica Read.

Additional behavior changes in 2.1.0 include:

• Backup, Restore and Transfer tool to optionally transfer data or design documents only. The default is to transfer both data and design documents. See cbbackup Tool, cbrestore Tool, cbtransfer Tool

• Improved cluster manager stability via separate process for cluster manager. See Underlying Server Processes.

• Command Line tools updated so you can manage nodes, buckets, clusters and XDCR. See couchbase-cli Tool

• More XDCR Statistics to monitor performance and behavior of XDCR. See Monitoring Outgoing XDCR.

• Command Line tools updated so you can manage nodes, buckets, clusters and XDCR. See couchbase-cli Tool.

• Several new and updated statistics for XDCR on the admin Console and via the REST API. For more information, see Monitoring Incoming XDCR, Monitoring Outgoing XDCR, and Getting XDCR Stats via REST.

Fixes in 2.1.0

• Installation and Upgrade

  • In the past Couchbase Server 2.0.0 upgrade installers on Linux did not replace the file2.beam with the latest version. This will cause indexing and querying to fail. This has been fixed.

    Issues : MB-7770

  • The Windows installer for Windows 32-bit and 64-bit now prompts you to set the MaxUserPort registry setting. This will increase the number of ephemeral ports available to applications on Windows, as documented in Microsoft Knowledge Base Article 196271. The installer also warns you that a reboot is necessary for this change to take effect. If this registry key is not set, it may lead to port exhaustion leading to various problems, see as MB-8321. For installer instructions, see Microsoft Windows Installation.

    Issues : MB-8321

• Cluster Operations

  • Previously, there was only one process that was responsible for monitoring and managing all the other underlying server processes. This includes Moxi and memcached, and also statistics gathering. Now there are two processes. One is responsible for just Moxi/Memcached and the other is responsible for monitoring all other processes. This should help prevent the max_restart_intensity seen when timeouts start and temporarily disrupted the server. The most noticeable change you see with this fix is that there are now two beam.smp processes running on Linux and two erl.exe running on Windows. For more details, see Underlying Server Processes.

    Issues : MB-8376

• Command-line Tools

  • For earlier versions of Couchbase Server, some internal server directories were accessible all users, which was a security issue. This is now fixed. The fix now means that you should have root privileges when you run cbcollect_info because this tool needs this access level to collect all the information it needs to collect about the server. For more information about cbcollect_info, see cbcollect_info Tool.

  • One XDCR REST API endpoint had a typo which is now fixed. The old endpoint was /controller/cancelXCDR/:xid. The new, correct endpoint is /controller/cancelXDCR/:xid. See Deleting XDCR Replications.

    Issues : MB-8347

  • In the past when you used cbworkloadgen you see this error ImportError: No module named _sqlite3. This has been fixed.

    Issues : MB-8153

• Indexing and Querying

  • In the past too many simultaneous views requests could overwhelm a node. You can now limit the number of simultaneous requests a node can receive. For more information, see REST API, see Limiting Simultaneous Node Requests.

    Issues : MB-8199

• Cross Datacenter Replication (XDCR)

  • When you create a replication between two clusters, you may see two error messages: “Failed to grab remote bucket info, vbucket” and “Error replicating vbucket X”. Nonetheless, replication will still start and then function as expected, but the error messages may appear for some time in the Web Console. This has been fixed.

    Issues : MB-7786, MB-7457

Known Issues in 2.1.0

• Installation and Upgrade

  • On Ubuntu if you upgrade from Couchbase Server 2.0 to 2.1.0 and use a non-default port, the upgrade can fail and return the message ‘Failed to stop couchbase-server.’ We recommend you use the default ports on both 2.0 and 2.1.0 when you perform an upgrade.

    Issues : MB-8051

  • You may have a installation of Couchbase Server with a custom data path. If you perform a server uninstall and then upgrade to 2.1.0 with the same custom data path, some older XDCR replication files may be left intact. This will result in server crashes and incorrect information in Web Console. The workaround for this case is to make sure you manually delete the _replicator.couch.1 file from the server data directory before you install the new version of the server. Alternately you can delete the entire data directory before you install the new version of the server. If you choose this workaround, you may want to backup your data before you delete the entire directory. By default, on Linux this directory is at /opt/couchbase/var/lib/couchbase/data/ and on Windows at C:/Program Files/Couchbase/Server/var/lib/couchbase/data/.

    Issues : MB-8460

• Database Operations

  • On Windows platforms, statistics from the server will incorrectly show a very high swap usage rate. This will be resolved in future releases of Couchbase Server.

    Issues : MB-8461

  • If you edit a data bucket using the REST API and you do not provide existing values for bucket properties, the server may reset existing bucket properties to the default value. To avoid this situation you should specify all existing bucket properties as well as the updated properties as parameters when you make this REST request. For more information, see Couchbase Manual, Creating and Editing Data Buckets.

    Issues : MB-7897

  • Any non-UTF-8 characters are not filtered or logged by Couchbase Server. Future releases will address this issue.

    Issues : MB-8427

• Cluster Operations

  • If you query a view during cluster rebalance it will fail and return the messages “error Reason: A view spec can not consist of merges exclusively” and then “no_active_vbuckets Reason: Cannot execute view query since the node has no active vbuckets.” The workaround for this situation is to handle this error and retry later in your code. Alternatively the latest version of the Java SDK will automatically retry upon these errors.

    Issues : MB-7661

  • If you perform asynchronous operations from a client to Couchbase on Windows, you may receive unclear status messages due to character encoding issues on Windows. This impacts status messages in the response only; actual response data is unaffected by this problem. This will be resolved in future releases of Couchbase Server.

    Issues : MB-8149

  • By default most Linux systems have swappiness set to 60. This will lead to overuse of disk swap with Couchbase Server. Please follow our current recommendations on swappiness and swap space, see Swap Space.

    Issues : MB-7737, MB-7774

  • A cluster rebalance may exit and produce the error {not_all_nodes_are_ready_yet} if you perform the rebalance right after failing over a node in the cluster. You may need to wait 60 seconds after the node failover before you attempt the cluster rebalance.

    This is because the failover REST API is a synchronous operation with a timeout. If it fails to complete the failover process by the timeout, the operation internally switches into a asynchronous operation. It will immediately return and re-attempt failover in the background which will cause rebalance to fail since the failover operation is still running.

    Issues : MB-7168

  • Stats call via Moxi are currently enabled, however if you use the command-line tool cbstats through Moxi on port 11211 to Couchbase Server, you will receive incorrect server statistics. To avoid this issue you should use port 11210 when you make a cbstats request.

    Issues : MB-7678

  • If you perform a scripted rolling upgrade from 1.8.1 to 2.1.0 nodes, you should script a delay of 10 seconds after you add a node and before you request rebalance. Without this delay, you may request rebalance too soon and rebalance may fail and produce an error.

    Issues : MB-8094

• Command-line Tools

  • cbbackup will backup even deleted items from a cluster which are not needed. In future releases it will ignore these items and not back them up.

    Issues : MB-8377

  • cbstats will not work on port 11210 if you installed Couchbase Server without root-level permissions.

    Issues : MB-7878

• Indexing and Querying

  • If you rebalance a cluster, index compaction starts but bucket compaction will not start. This is because vBucket cleanup from an index is not accounted for in index fragmentation. After this cleanup process completes it will cause more index fragmentation and therefore we run compaction again. Index compaction will therefore always run after a certain number of changes to vBuckets on nodes. You can change this setting using the REST API, see Adjusting Rebalance during Compaction.

    Issues : MB-8319

• Performance

  • RHEL6 and other newer Linux distributions running on physical hardware are known to have transparent hugepages feature enabled. In general this can provide a measurable performance boost. However under some conditions that Couchbase Server is known to trigger, this may cause severe delays in page allocations. Therefore we strongly recommend you disable this feature with Couchbase Server.

    Issues : MB-8456

Couchbase Server Release Notes for 2.0.1 GA (March 2013)¶

The following sections provide release notes for individual release versions of Couchbase Server.

Couchbase Server 2.0.1 is first maintenance release for Couchbase Server 2.0. This release contains number of enhancements particularly for the rebalance, indexing and compaction operations. In addition, it also includes some critical bug fixes related to system timeouts and system stability. This includes:

• Improves rebalance operation time for key-value use cases.

• Improves coordination of index compaction and index building that occurs during the rebalance operation. This helps significantly reduce the index file size growth during rebalance.

• Changes to high and low water marks that provides more usable memory for users.

• Fixes timeout problems that were seen due to Erlang VM settings.

• Fixes a critical indexing problem. A document that produced a runtime failure in one view had been unavailable to all other views within the same design document.

Fixes in 2.0.1

To browse the issues, see Couchbase Server Issues Tracker. * Installation and Upgrade

* We now provide a warning message on minimal system requirements for Couchbase
  Server. This appears on Linux in the terminal, and on Windows as a InstallShield
  screen. For more information about minimum platform requirements, see the
  section [Preparation](#couchbase-getting-started-prepare).

  *Issues* : [MB-7482](http://www.couchbase.com/issues/browse/MB-7482)

• Cluster Operations

  • The server had experienced timeouts during rebalance if views were being indexed or compacted at the same time. This resulted in the rebalance to fail. This has been fixed.

    Issues : MB-6595

  • In the past, if you were performing an online upgrade of a 1.8 cluster to 2.0 by adding 2.0 nodes, the dynamic configuration file on 2.0 nodes would be purged. This resulted in any XDCR remote cluster references to be lost on the 2.0 nodes and would produce this error message "case_clause,error". This is now fixed.

    Issues : MB-7568

  • The server had experienced random timeouts possible due to lack of asynchronous I/O threads. This caused rebalance to fail. This has been fixed.

    Issues : MB-7182

• Command-line Tools

  • There is a new setting available in cbepctl named mutation_mem_threshold. This is the amount of RAM that can be used on the server before a client begins receiving temporary out of memory errors. For more information, see Changing Setting for Out Of Memory Errors.

    Issues : MB-7540

• Indexing and Querying

  • In past releases of Couchbase Server 2.0, if you had a map function that failed to index, other functions in the same design document would also fail. This has been fixed.

    Issues : MB-6895

  • During rebalance, index files were growing to an unnecessarily large size. This has been fixed.

    Issues : MB-6799

  • There is a new REST API call which can be used if you experience a slow rebalance while indexing and compaction are in progress. For more information, see Adjusting Rebalance during Compaction.

    Issues : MB-7843

• Cross Datacenter Replication (XDCR)

  • Stats for XDCR had erroneously omitted the time taken to commit items and had also displayed the incorrect number of documents/mutations checked and replicated. This is fixed.

    Issues : MB-7275

  • When you create a replication between two clusters, you may see two error messages: “Failed to grab remote bucket info, vbucket” and “Error replicating vbucket X”. Nonetheless, replication will still start and then function as expected, but the error messages may appear for some time in the Web Console. This has been fixed.

    Issues : MB-7786, MB-7457

Known Issues in 2.0.1

To browse or submit new issues, see Couchbase Server Issues Tracker.

• Installation and Upgrade

  • When you upgrade from Couchbase Server 2.0.0 to 2.0.1 on Linux the install may not replace the file2.beam with the latest version. This will cause indexing and querying to fail. The workaround is to install 2.0.1 and then manually restart Couchbase Server with the following commands:

    sudo /etc/init.d/couchbase-server stop
     sudo /etc/init.d/couchbase-server start
    

    Issues : MB-7770

    • If you perform an online upgrade from Couchbase Server 2.0.0 to 2.0.1, rebalance may exit with the error:

      {{{linked_process_died,….,normal},
       {gen_server,call,
       [‘capi_set_view_manager-sasl’,
       {set_vbucket_states,
      

      Issues : MB-7771

• Database Operations

  • In OpenVZ Linux containers, the server had crashed and restarted when you created a Couchbase bucket. This was due to an issue in the memsup process from Erlang. To fix this issue, you should upgrade to the latest version of Erlang, and have Couchbase Server use this version:

    1. Stop Couchbase Server.

    2. Make a copy of your original memsup then get the patch available on GitHub: memsup patch.

    3. Place the compiled code in /opt/membase/lib/erlang/lib/os_mon-2.2.5/priv/bin/.

    4. Start Couchbase Server.

    Issues : MB-7626

• Cluster Operations

  • If you query a view during cluster rebalance it will fail and return the messages “error Reason: A view spec can not consist of merges exclusively” and then “no_active_vbuckets Reason: Cannot execute view query since the node has no active vbuckets.” The workaround for this situation is to handle this error and retry later in your code. Alternatively the latest version of the Java SDK will automatically retry upon these errors.

    Issues : MB-7661

  • If you want to add a new Couchbase Server 2.0.1 node to a running 2.0 cluster, and you want to refer to this node by hostname do the following on the new node:

    • On Linux: create a file named ip_start in the directory /opt/couchbase/var/lib/couchbase for the node. In this new file, add a line provides the DNS name or IP address that you want to use to refer to the node.

    • On Windows: create a file named ip_start in the directory c:\program files\couchbase\server\var\lib\couchbase for the node. In this new file, add a line provides the DNS name or IP address that you want to use to refer to the node.

    For more information, see Couchbase Manual 2.0, Node Upgrade Process.

    Issues : MB-7664

  • By default most Linux systems have swappiness set to 60. This will lead to overuse of disk swap with Couchbase Server. Please follow our current recommendations on swappiness and swap space, see Swap Space.

    Issues : MB-7737, MB-7774

  • If you try to add a node during cluster rebalance, the rebalance may fail and return the messages {detected_nodes_change or {ns_node_disco_events. To avoid this error complete your cluster rebalance, add the new node and then rebalance once again. This issue will be fixed in future releases.

    Issues : MB-6280

  • A cluster rebalance may exit and produce the error {not_all_nodes_are_ready_yet} if you perform the rebalance right after failing over a node in the cluster. You may need to wait 60 seconds after the node failover before you attempt the cluster rebalance.

    This is because the failover REST API is a synchronous operation with a timeout. If it fails to complete the failover process by the timeout, the operation internally switches into a asynchronous operation. It will immediately return and re-attempt failover in the background which will cause rebalance to fail since the failover operation is still running.

    Issues : MB-7168

• Indexing and Querying

  • If you have a large amount of data in Couchbase Server and also use views, data compaction and views compaction may not automatically start. If you encounter this issue, you should change your node settings so that data and views compaction will start in paralell. In Couchbase Web Console: Select Settings | Auto-Compaction | Process Database and View compaction in paralell.

    Issues : MB-7781

• Cross Datacenter Replication (XDCR)

  • You may experience an uneven rate of replication for nodes in a cluster. This is intermittent behavior that is due to different disk drain rates at different nodes and will subside by itself over time. There is no need to change any settings on your cluster to try to resolve this behavior.

    Issues : MB-7657

Release Notes for Couchbase Server 2.0.0 GA (December 12 2012)¶

Couchbase Server is a NoSQL document database for interactive web applications. It has a flexible data model, is easily scalable, provides consistent high performance and is “always-on,” meaning it can serve application data 24 hours, 7 days a week. For more information about Couchbase Server 2.0, visit Couchbase Server 2.0.

The major new features available in Couchbase Server 2.0 include:

• Flexible data model. Couchbase provides a schema-less, JSON-based data model which is more efficient and intuitive to work with compared to the fixed-schema approach used by RDBMS. With JSON you can use different structures for application objects; it is much easier to represent complex data, and you can add new types of data without having to go through typical schema migration.

• Indexing and Querying. With Couchbase Server 2.0, you can easily find documents and perform calculations on your data by using views in 2.0. Indexes can be defined using JSON and JavaScript functions. Once you have defined your functions you can query the information or perform calculations on the information using Couchbase Web Console or a Couchbase SDK.

• Incremental Map/Reduce. Couchbase Server supports incremental index building, meaning it only re-indexes documents that have been changed since the last index update. Instead of recomputing index results from the beginning every time data changes in your database, Couchbase Server stores intermediate results in the index and can recalculate this data only when necessary. This means you do not need to wait for a batch job across the entire data set to finish each time you want to see your results.

• Cross Data Center Replication (XDCR). In 2.0, we add cross data center replication which enables you to replicate data from one cluster to another one so that your data is always available 24x365. It provides you with an easy way to replicate active data uni-directionally or bi-directionally between multiple data centers in different geographical areas. This provides you a copy of your data for disaster recovery and can help you bring your data closer to your end users for better application performance.

New Features and Behavior Changes in 2.0.0

• XDCR (Cross Data-Center Replication) Enhancements.

  This includes the following features and enhancements:

  • Performance improvements. Performance for outbound replication from a source cluster to a destination has been improved. CPU utilization on destination clusters has been reduced for better performance.

  • Improved Error Handling and Logging. More information about documents and the size of documents awaiting replication now available.

  • UI Improvements for XDCR in the Couchbase Web Console.

  The Couchbase Web Admin Console has been expanded to show the number of documents waiting to be replicated via XDCR and the total size of all documents waiting for replication. Low-level errors and statistics have been moved to a Couchbase Web Console log file to avoid information overload and confusion. Messages that are more appropriately categorized as recoverable states have been labeled warnings, not errors.

• New sample data buckets are available to get you started with Couchbase Server 2.0. The new buckets include sample documents as well as views so you play around with the new Couchbase Server 2.0 features.

• Online compaction for data and indexes, which kicks off based on fragmentation thresholds. You can configure these thresholds along with the compaction schedule. In addition, the UI gives you more visibility into background compaction. For more information, see Auto-Compaction Configuration.

• There is also now a new REST API in Couchbase Server 2.0 where you can enable or disable flush for each data bucket in a cluster. This also enables you to flush an individual bucket in a cluster or multiple buckets on a cluster with a single REST API command. For more information, see Flushing a Bucket.

  Issues : MB-6776

• Improve and enable data flush for entire cluster via individual data buckets. Ability to disable and enable the configuration setting for safe cluster administration. For more information, see Editing Couchbase Buckets.

• New command-line tools, and consolidated tools provided in new locations. This is to simplify your use of these tools. For more information about these improvements, and the location of new tools, see Command Line Tools and Availability.

• Improved working set management. When your working set of documents becomes larger than allocated memory, the system needs to eject documents. Couchbase now tracks recently accessed, updated or inserted documents and ejects “not recently used” documents from RAM. This working set metadata is also replicated so that after a rebalance operation, your working set is maintained on the new nodes in the cluster for reduced latencies post rebalance.

• Server logs have been split and have been provided logical naming. This makes it easier for you to spot or diagnose server issues. For more information, see Logs and Logging.

• Querying Views during Rebalance.

  If you perform queries during rebalance, this new feature will ensure that you receive the query results that you would expect from a node as if it is not being rebalanced. During node rebalance, you will get the same results you would get as if the data were on an original node and as if data were not being moved from one node to another. In other words, this new feature ensures you get query results from a new node during rebalance that are consistent with the query results you would have received from the node before rebalance started.

  With this new feature, you will get the same query results before rebalance, during rebalance and after rebalance. Without this new functionality querying a view during rebalance would have provided results inconsistent with the results from a source node. With this new functionality enabled, data that is being moved from one node to another node will be incrementally added to an index available at the new node so that you get query results that are consistent with your expectations.

• New append-only persistence engine. This improves disk write performance as updates are written only to the end of the file. Additional disk resources are required..

• Shorter server warm-up time. When Couchbase Server is restarted, or when it is started after an offline recovery from backup, the server goes through a warm-up process first loading metadata from disk into RAM. Additionally, it loads the documents that belong to the tracked working set maintained in an access log. This reduces warm-up time and also makes the most relevant data available instead of sequentially loading all data into RAM.

• General Changes in Rebalance Behavior.

  During rebalance, Couchbase Server now has new internal logic that will wait for data to be persisted at a new node before the new node takes responsibility for serving the data. In situations where you want a very high level of durability, this can provide you more assurance that your data can be recovered after node failures.

Fixes in 2.0.0

• Database Operations

  • Now provide timestamp for when a TAP queue backfill starts. The TAP backfill queue is used to send a snapshot of a vbucket to another node.

    Issues : MB-6753

  • Couchbase Server had created new checkpoints even in the case where empty, current checkpoints were available. The server provided extraneous notifications when various changes to checkpoints ID occurred due to constant polling by XDCR. Now when an empty checkpoint is available, the server uses this checkpoint for additional replication and provide this checkpoint ID to XDCR. The server also pushes a single notification to XDCR when a checkpoint is empty.

  • In the past if you set the disk path for data to be the same path as that for index files, Couchbase Server would fail to start. This is fixed.

    Issues : MB-6995

  • In the past, if you used a symbolic link to reference a data directory for Couchbase Server, the server determined remaining free only for the partition that contained the symbolic link. This resulted in two issues: 1) incorrect information in the Couchbase Web Console, 2) more significantly, it would accidentally inhibit the data compaction process because of incorrect information about free disk space. This has been fixed in 2.0.

    Issues : MB-7307

  • During Couchbase Server warmup or rebalance, if you delete a data bucket, it will cause the node to crash.

    Issues : MB-7272

  • Performing a touch operation and providing an expiration of 0, to indicate no expiration did not function. This is now fixed.

    Issues : MB-7342

  • We now log all vBucket state changes as mccouch events.

    Issues : MB-7057

  • To handle current limitations on open file descriptors allowed on MacOS, the number of vBuckets on MacOS have been reduced to 64 from 1024. This reduces the number of files that are created for data as well as for indexes. Overall this provides improved CPU and disk I/O for MacOS.

    Note however that replication via XDCR between a MacOS and non-MacOS servers will not work due to the mismatch in the number of vBuckets between Mac OSX and other platforms.

    In addition mixed clusters with Couchbase nodes running on Mac OSX and on non-Mac OSX platforms will not function. In general Mac OSX is supported by Couchbase only for developing with Couchbase Server and not for production.

    Issues : MB-6781

  • Check-and-set value was not returned in response to a successful delete request. Now it is returned as part of the response.

    Issues : MB-6661

  • In the past, the server would delete items even if a provided CAS value was a mismatch. This has been fixed.

    Issues : MB-6985

• Cluster Operations

  • Get-and-touch function were not providing the correct error information from the server. Get-and-touch now returns ENOENT if key does not exist.

    Issues : MB-6840

  • The Couchbase REST API has changed to enable you to change the default maximum number of buckets used in a Couchbase cluster. The maximum allowed buckets in this request is 128, however the maximum suggested number of buckets is ten per cluster. This is a safety mechanism to ensure that a cluster does not have resource and CPU overuse due to too many buckets. The following illustrates the endpoint and parameters used:

    shell>    curl -X -u admin:password -d maxBucketCount=6 http://ip_address:8091/internalSettings
    

    For this request you need to provide administrative credentials for the cluster. The following HTTP request will be sent:

    About to connect() to 127.0.0.1 port 8091 (#0)
       Trying 127.0.0.1…
       connected
       Connected to 127.0.0.1 (127.0.0.1) port 8091 (#0)
       Server auth using Basic with user ‘Administrator’
       POST /internalSettings HTTP/1.1
    

    If Couchbase Server successfully changes the bucket limit for the cluster, you will get a HTTP 200 response:

    HTTP/1.1 200 OK
       Server: Couchbase Server 2.0.0r_501_gb614829
       Pragma: no-cache
       Date: Wed, 31 Oct 2012 21:21:48 GMT
       Content-Type: application/json
       Content-Length: 2
       Cache-Control: no-cache
    

    If you provide an invalid number, such as 0, a negative number, or an amount over 128 buckets, you will get this error message:

    ["Unexpected server error, request logged."]
    

    For more information about setting buckets per cluster via REST API, see Setting Maximum Buckets for Clusters.

    Issues : MB-5684

• Web Console

  • We have removed the automatic 5-minute timeout for Couchbase Web Console. This inhibited people from performing ongoing work and demonstrations of the server.

  • For Mac OSX, we had provided a drop-down UI menu for logs that pointed to the wrong location. This menu option has been removed since it is already provided in the Web Console.

    Issues : MB-7075

  • We now provide memcached logs in the diagnostic reports available from the Couchbase Web Console.

    Issues : MB-7048

• Command-line Tools

  • Several command line tools have been deprecated, superceded, or moved. This includes cbflushctl which has been superceded by cbepctl. For more information, see Command-line Interface for Administration.

    Issues : MB-6912

  • For Mac OSX, the tool for collecting statistics for Couchbase technical support cbcollect_info was not functioning. We have fixed it.

    Issues : MB-6958

  • Incorrect message had been sent in response to a cbstats vkey command. Server had returned the string ‘not found’ for valid request. Now correct the memcached protocol error is returned. For more information about cbstats, see cbstats Tool.

    Issues : MB-6751

  • cbepctl help options now show option for setting the expiry_pager, a maintenance process for removing deleted items from disk.

    Issues : MB-6764

• Cross Datacenter Replication (XDCR)

  • Fix rebalance timeout failure during unidirectional replication of items via XDCR. Failure had returned message: “timeout, ns_memcached-bucket',‘ns_1@10.1.3.238’}, {get_vbucket,”.

    Issues : MB-6493

  • Errors had occurred performing replication via XDCR due to improper handling of non- UTF-8 characters. We now handle errors due to non- UTF-8 characters and can continue replication via XDCR for JSON documents containing non- UTF-8.

    Issues : MB-7092

  • We have added 3 new outbound operation stats, namely, 1) data replicated, which is amount of data XDCR have replicated to the remote data center through inter- cluster network; 2) active vb replications, which shows the number of ongoing active replications to the remote clusters; 3) waiting vb replications, which is the number of vb replications in the waiting pool to wait for turn to start replication. These stats will be useful for performance monitoring and diagnosis.

    Issues : MB-6919

  • By default, the server automatically disables flushing data from a source data bucket when XDCR replications exist for that bucket.

    Issues : MB-6809

Known Issues in 2.0.0

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • By default when you perform a new install of Couchbase Server 2.0, creating a replica index for a data bucket is disabled by default. This should be the standard default setting for all new installs of the server. However, when you upgrade from 1.8.1 to 2.0, be aware it is enabled by default.

    Issues : MB-7339

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • In order to upgrade from 1.8.1 to 2.0 for the Microsoft Windows platform, you need to make changes to the ip file located on the node at Couchbase\Server\var\lib\couchbase\ip as well as complete some additional steps on your node which will apply whether you are using Windows on the cloud or not. For more information about upgrading from 1.8.x to 2.0, see Upgrades Notes 1.8.1 to 2.0 +.

    Issues : MB-7289

    For more information, see Handling Changes in IP Addresses.

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

  • Performing an upgrade from Couchbase 1.8.1 to Couchbase 2.0.0 GA build freezes while transferring data from SQLite files to Couchstore files using cbtransfer.

    Issues : MB-7341

  • If you use couchbase-cli to setup a Couchbase node on a non-default port, you may receive an error. Although the cluster gets initialized, the initial RAM quota is not used and the server returns an error.

    Issues : MB-7268

  • On Ubuntu 64-bit 12.04, when you upgrade Couchbase Server from 1.8.1 to 2.0 the upgrade will work, however the server erroneously returns an error in the end when it starts. The error is: “Failed to start couchbase-server dpkg: error processing couchbase-server (‐‐install)”. Ignore this error message.

    Issues : MB-7298

• Database Operations

  • Several incidents have been reported that after using Flush on nodes, Couchbase Server returns TMPFAIL even after a successful flush.

    Issues : MB-7160

  • For the Windows platform, attempts to perform a rebalance of a restarted node fails due to failure to clean up old data buckets on the node. The workaround is to retry the rebalance.

    Issues : MB-7202

  • If you reset the disk path to a path that contained corrupted data, Couchbase Server will shut down and non response. When you change the data path to a different folder, make sure it does not contain files with a different format or with incorrect permissions.

    Issues : MB-7185

  • Be aware that you may experience delays while node is in a pending state after you change the index path for that node. This will be fixed in a point release after 2.0 GA.

    Issues : MB-7337

• Cluster Operations

  • If you query a view during cluster rebalance it will fail and return the messages “error Reason: A view spec can not consist of merges exclusively” and then “no_active_vbuckets Reason: Cannot execute view query since the node has no active vbuckets.” The workaround for this situation is to handle this error and retry later in your code. Alternatively the latest version of the Java SDK will automatically retry upon these errors.

    Issues : MB-7661

  • During a rebalance operation for clusters undergoing uni- and bi-directional replication via XDCR, the following server errors may appear, which are currently under investigation:

    Server error during processing: ["web request failed",
     {path,"/pools/default"},
     {type,exit},
     {what,
     {timeout,
     {gen_server,call,
     [ns_doctor,get_tasks_version]}}},
     {trace,
     [{gen_server,call,2},
     {menelaus_web,build_pool_info,4},
     {menelaus_web,handle_pool_info_wait,5},
     {menelaus_web,loop,3},
     {mochiweb_http,headers,5},
     {proc_lib,init_p_do_apply,3}]}] (repeated 1 times)
    

    Issues : MB-7286

    • By default most Linux systems have swappiness set to 60. This will lead to overuse of disk swap with Couchbase Server. Please follow our current recommendations on swappiness and swap space, see Swap Space.

      Issues : MB-7737, MB-7774

    • One of the internal maintenance processes within Couchbase Server for checking vBuckets will stop node rebalance when you create replication via XDCR on a source cluster.

      A node in a cluster may also stop rebalance when another node orchestrating rebalances is over loaded. When a node stops rebalance, it results in the error message “Resetting rebalance status since it is not really running”.

      Rebalance cna also fail due to the timeout in bulk_set_vbucket_state operation with continuous view queries.

      Issues : MB-6481, MB-6573, MB-7212

• Web Console

  • The Couchbase Web Console will erroneously clear all summary statistics for a data bucket when a new index is being generated in the background. The workaround is to reload the page to get the current statistics.

    Issues : MB-7090

  • Be aware that if attempt hundreds of simultaneous queries with an unlimited number of results, Couchbase Server may fail. If you have a result set from indexing that contains 10 million items or more, and you query for that entire result set, the server will fail.

    Instead you should specify a reasonable limit of results when you query, such as retriving a range of results from the larger set, otherwise the server will stall and crash due to excessive memory usage. For more information about querying and specifying a subset of results, see Querying Views.

    Issues : MB-7199

  • If you have a cluster running Couchbase Server 1.8.1 and 2.0.0, Couchbase Web Console 2.0 will show incorrect, sometimes negative values for Disk Usage in the summary section. Ignore this error.

    Issues : MB-7183

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • The sample data loader will fail to run on a cluster when the cluster contains nodes with different versions of Couchbase. The workaround is to upgrade all cluster nodes to Couchbase Server 2.0. For more information about upgrading nodes from 1.8.x to 2.0, see Upgrades Notes 1.8.1 to 2.0 +.

    Issues : MB-7171

  • The couchbase command line tool, couchbase-cli does not enable you to set index_path as a separate parameter as data_path. The former contains indexed data from defined views functions, while the later contains keys, metadata, and JSON documents. You can however use the REST API to do this.

    Issues : MB-7323

    For more information, see Configuring Index Path for a Node.

  • The sample data loader will also fail if there are multiple nodes in a cluster and creating a bucket in the cluster is taking longer than 10 seconds.

    Issues : MB-7170

• Indexing and Querying

  • If you are using development views, be aware you may see inconsistent results if you query a development view during rebalance. For production views, you are able to query during rebalance and get results consistent with those you would have recieved if no rebalance were occurring.

    Issues : MB-6967

  • Accessing a recently created view (with other, existing active views) may return a error if the corresponding design document and view definition have not been replicated across the cluster. The error return will be returned in error of the view output detailing the missing design document. The workaround is to add views and design documents to your node or cluster after you have performed rebalance. For more information about resolving issues with Couchbase Views, see Troubleshooting Views (Technical Background).

    Note also that stopping a rebalance operation on a cluster may take a long time if compaction and indexing operations are in progress on the cluster at the point of rebalance. Again, the workaround is to add views and index and query views after you have performed compaction or rebalance. For more information about rebalance, and considerations on when to rebalance, see Rebalancing.

    Issues : MB-6726, MB-6339

  • If a map function in a design document fails while processing a document, that document will also not be computed for any other map functions in the same design document. To avoid creating errors in your views functions, see the tips and advice provided in Troubleshooting Views (Technical Background).

    Issues : MB-6895

  • Couchbase Server does lazy expiration, that is, expired items are flagged as deleted rather than being immediately erased. Couchbase Server has a maintenance process that will periodically look through all information and erase expired items. This means expired items may still be indexed and appear in result sets of views. The workarounds for this behavior are available here About Document Expiration.

    Issues : MB-7053

• Cross Datacenter Replication (XDCR)

  • beam.smp memory usage grows to 2 GB when XDCR feature is enabled and rebalancing is in progress.

    Issues : MB-6649

  • Under the XDCR tab for Couchbase Web Console, the link to a a destination cluster takes you to a missing URL. A simple workaround is to append ‘:8091’ to the address in the newly opened browser tab.

    Issues : MB-7211

  • Replication rat e may drop when the XDCR replication queue size becomes less than 500 items.

    Issues : MB-6586

  • Be aware that if you are using XDCR for replication to a destination bucket and you remove and create a new bucket with the same name, it has a different UUIDs. Therefore any replication you had established with the deleted bucket will not apply to the new bucket.

    Issues : MB-7262

• Performance

  • Under a heavy load of write operations on two clusters and both bi-directional and uni-directional replications occurring via XDCR, Couchbase Server 2.0 may fail during rebalance.

    Issues : MB-7290

  • ep-engine needs 1.5 minutes to create 1024 vbuckets. This may be too slow, however performance improves with setting barrier=0.

    Issues : MB-6232

Release Notes for Couchbase Server 2.0.0 #1941 Beta (November 13 2012)¶

This is build #1941 of Couchbase Server 2.0. Couchbase Server is a NoSQL document database for interactive web applications. It has a flexible data model, is easily scalable, provides consistent high performance and is “always-on,” meaning it can serve application data 24 hours, 7 days a week. For more information about Couchbase Server 2.0, visit Couchbase Server 2.0.

The major improvements made between build #1870 and build #1941 are described below:

New Features and Behavior Changes in 2.0.0 #1941

• The default node quota percentage has been reduced from 80% to 60% to provide capacity in the operating system for the view and indexing data to be cached.

  Issues : MB-6973

Fixes in 2.0.0 #1941

• Installation and Upgrade

  • For Mac OSX, we provide the correct version number in the README.

    Issues : MB-6697

• Database Operations

  • The default timeout for persisting a checkpoint had been 10 seconds. This default is still in place, but will now be adjusted upward or downward by the server to be the last duration required to persist a checkpoint. This is to better optimize server resources for indexing during rebalance.

    Issues : MB-6976

  • In the past, we declared the revision value for a document to be 32- bit value and have changed this to 48- bit value. This is to support a larger number of document revisions and to support conflict resolution in XDCR.

    Issues : MB-6945

  • Document revision numbers had been stored as 32 bit values but are now stored as larger 48 bit values. This enables more documents to be changed or deleted for the same database shard. A Couchbase cluster can run for more than three years performing 400,000 operations a second until revision sequence limits are met. This change is to support the functioning of XDCR and to support a larger number of document revisions.

    This fix changes the on-disk data format. You will not be able to use data files from prior builds of Couchbase Server 2.0 on this new build.

    Issues : MB-6945

  • For Windows, rebalanced has exited due to some concurrent file operations that are not allowed on this platform. This has been fixed by enabling retry of file operations for Windows during rebalance.

    Issues : MB-6945

  • Document revision numbers had been stored as 32 bit but are now stored as 48 bit values. This is to support the functioning of XDCR and to support a larger number of document revisions.

    Issues : MB-6945

  • By default we now provide garbage collection more frequently than the normal default for Erlang. This keeps memory usage by the Erlang virtual machine lower, and enables better performance.

    Issues : MB-6974

  • We now provide more log information about errors during vBucket reset and deletion.

    Issues : MB-6494

  • Couchbase Server had intermittently crashed during rebalance due to Erlang virtual machine issues; we now disable asynchronous threads and perform garbage collection more often to avoid timeouts and process crashes.

    Issues : MB-6638

  • We now log all vBucket state changes as mccouch events.

    Issues : MB-7057

  • To handle current limitations on open file descriptors allowed on MacOS, the number of vBuckets on MacOS have been reduced to 64 from 1024. This reduces the number of files that are created for data as well as for indexes. Overall this provides improved CPU and disk I/O for MacOS.

    Note however that replication via XDCR between a MacOS and non-MacOS servers will not work due to the mismatch in the number of vBuckets between Mac OSX and other platforms.

    In addition mixed clusters with Couchbase nodes running on Mac OSX and on non-Mac OSX platforms will not function. In general Mac OSX is supported by Couchbase only for developing with Couchbase Server and not for production.

    Issues : MB-6781

  • In the past, the server would delete items even if a provided CAS value was a mismatch. This has been fixed.

    Issues : MB-6985

• Cluster Operations

  • Get-and-touch function were not providing the correct error information from the server. Get-and-touch now returns ENOENT if key does not exist.

    Issues : MB-6840

  • Server now releases returned document that is being marked deleted. This fixes a rebalance failure where memcached crashes on one of the nodes and rebalance exits with the error: {mover_failed,{badmatch, known macro: {error,closed}}}.

    Issues : MB-6806

  • Rebalanced had been delayed after failing-over a disconnected node. This is fixed.

    Issues : MB-6992

  • The Erlang virtual machine had intermittently crashed when adding a node and rebalancing. By increasing the checkpoint timeout for XDCR replication we have resolved the issue.

    Issues : MB-7056

• Web Console

  • We have removed the automatic 5-minute timeout for Couchbase Web Console. This inhibited people from performing ongoing work and demonstrations of the server.

  • In the past, clicking on a document name shown in the View Results panel did not load the document in the sample document pane. This has been fixed.

    Issues : MB-6500

  • A data request error had been returned when a user attempted to save spatial views containing map or reduce functions which could not compile. A new error handler has been added to display a more helpful message.

    Issues : MB-7029

  • We now refresh the available design documents in the Web Console when you move to the views section.

    Issues : MB-6978

  • We have removed the automatic 5-minute timeout for Couchbase Web Console. This was cumbersome and annoying for people performing ongoing work and demonstrations of the server.

    Issues : MB-6679

  • Number of documents per page specified in the top right corner on the Documents page of Couchbase Web Console does not match the number of documents actually presented to the user. This is fixed.

    Issues : MB-7011

  • The number of documents you can skip in the Web console is now 1000. This is to avoid overloading the user interface for a larger number of documents.

    Issues : MB-7067

  • For Mac OSX, we had provided a drop-down UI menu for logs that pointed to the wrong location. This menu option has been removed since it is already provided in the Web Console.

    Issues : MB-7075

  • We now provide memcached logs in the diagnostic reports available from the Couchbase Web Console.

    Issues : MB-7048

• Command-line Tools

  • Errors had occurred on windows trying to run Python workload generators. This has been fixed by adding the bin directory to the Python path.

    Issues : MB-7086

  • Errors had occurred trying to access design documents associated with buckets requiring SASL authentication. This has been fixed by properly requiring authorization information to access these buckets.

    Issues : MB-6757

  • For Mac OSX, the tool for collecting statistics for Couchbase technical support cbcollect_info was not functioning. We have fixed it.

    Issues : MB-6958

• Indexing and Querying

  • For geo/spatial indexes, which are experimental features in Couchbase 2.0, we now provide validation of spatial functions.

    Issues : MB-6990

  • For geo/spatial indexes, after updating a design document, or deleting a design document, the old index files and erlang processes were not released. This unnecessarily took disk space and resulted in leaking file descriptors. After database shard compaction, spatial/geo indexes would never release the file handle of the pre-compaction database files. This meant that disk space couldn’t be reclaimed by the OS. This has now been fixed.

    For general indexes, after index compaction the pre-compaction index files were deleted but were somtimes held open for a long time. This prevented the OS from reclaiming the respective disk space and leaking one file descriptor per index compaction. This has been fixed.

    For both geo/spatial and general indexes, we now avoid creating unnecessary empty index files and now avoid keeping them open for very long periods, such as waiting until bucket deletion. This is a more minor fix which helps decrease the number of open file descriptors, which is important if you are wroking on an operating sytem with a small limit of max allowed file descriptors, such as Windows and Mac OS X.

    Issues : MB-6860

  • For geo/spatial indexes, which are experimental features in Couchbase 2.0, we had erroneously returned a ‘node’ key in the result set which is debug information. This is now fixed.

    Note also that querying a spatial view will always return total_rows = 0 as part of the result set. This is information used for internal functioning of spatial views.

    Issues : MB-6942

  • For geo/spatial indexes, which are experimental features in Couchbase 2.0, we had experienced index file descriptor leaks. This is fixed.

    Issues : MB-6860

• Cross Datacenter Replication (XDCR)

  • Errors had occurred performing replication via XDCR due to improper handling of non- UTF-8 characters. We now handle errors due to non- UTF-8 characters and can continue replication via XDCR for JSON documents containing non- UTF-8.

    Issues : MB-7092

  • XDCR checkpoint intervals have increased to 30 minutes from 5 minutes. This helps increase the chance that a checkpoint will successfully replicate and not fail; this also reduces the frequent overhead required to determine if a checkpoint completed.

    Issues : MB-6939

  • XDCR had displayed error messages as if they were non-recoverable issues that required immediate attention. We now provide error messages with less dramatic color coding and label them as errors vs. urgent warnings.

    Issues : MB-6934

• Performance

  • Performance improvements have been made to reduce the time taken to rebalance when consistent query results are enabled for rebalances.

    Issues : MB-7030

Known Issues in 2.0.0 #1941

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

Release Notes for Couchbase Server 2.0.0 build #1870 Beta (1 November 2012)¶

This is build #1870 of Couchbase Server 2.0. Couchbase Server is a NoSQL document database for interactive web applications. It has a flexible data model, is easily scalable, provides consistent high performance and is “always-on,” meaning it can serve application data 24 hours, 7 days a week. For more information about Couchbase Server 2.0, visit Couchbase Server 2.0.

The major improvements made between Beta and build #1870 include:

• General Changes in Rebalance Behavior.

  During rebalance, Couchbase Server now has new internal logic that will wait for data to be persisted at a new node before the new node takes responsibility for serving the data. In situations where you want a very high level of durability, this can provide you more assurance that your data can be recovered after node failures.

• Querying Views during Rebalance.

  If you perform queries during rebalance, this new feature will ensure that you receive the query results that you would expect from a node as if it is not being rebalanced. During node rebalance, you will get the same results you would get as if the data were on an original node and as if data were not being moved from one node to another. In other words, this new feature ensures you get query results from a new node during rebalance that are consistent with the query results you would have received from the node before rebalance started.

  With this new feature, you will get the same query results before rebalance, during rebalance and after rebalance. Without this new functionality querying a view during rebalance would have provided results inconsistent with the results from a source node. With this new functionality enabled, data that is being moved from one node to another node will be incrementally added to an index available at the new node so that you get query results that are consistent with your expectations.

• XDCR (Cross Data-Center Replication) Enhancements.

  This includes the following features and enhancements:

  • Performance improvements. Performance for outbound replication from a source cluster to a destination has been improved. CPU utilization on destination clusters has been reduced for better performance.

  • Improved Error Handling and Logging. More information about documents and the size of documents awaiting replication now available.

  • UI Improvements for XDCR in the Couchbase Web Console.

  The Couchbase Web Admin Console has been expanded to show the number of documents waiting to be replicated via XDCR and the total size of all documents waiting for replication. Low-level errors and statistics have been moved to a Couchbase Web Console log file to avoid information overload and confusion. Messages that are more appropriately categorized as recoverable states have been labeled warnings, not errors.

• Improve and enable data flush for entire cluster via individual data buckets. Ability to disable and enable the configuration setting for safe cluster administration. For more information, see Editing Couchbase Buckets.

• Server logs have been split and have been provided logical naming. This makes it easier for you to spot or diagnose server issues. For more information, see Logs and Logging.

New Features and Behavior Changes in 2.0.0 build #1870

• There is also now a new REST API in Couchbase Server 2.0 where you can enable or disable flush for each data bucket in a cluster. This also enables you to flush an individual bucket in a cluster or multiple buckets on a cluster with a single REST API command. For more information, see Flushing a Bucket.

  Issues : MB-6776

Fixes in 2.0.0 build #1870

• Database Operations

  • Now provide timestamp for when a TAP queue backfill starts. The TAP backfill queue is used to send a snapshot of a vbucket to another node.

    Issues : MB-6753

  • Couchbase Server had created new checkpoints even in the case where empty, current checkpoints were available. The server provided extraneous notifications when various changes to checkpoints ID occurred due to constant polling by XDCR. Now when an empty checkpoint is available, the server uses this checkpoint for additional replication and provide this checkpoint ID to XDCR. The server also pushes a single notification to XDCR when a checkpoint is empty.

    Issues : MB-6632

  • Couchbase Server kept requesting to mark a group of partitions as indexable when they were already marked as indexable, or when they are already correctly marked as unindexable. This triggered redundant effort by processes. It is now fixed.

    Issues : MB-6804

  • During XDCR replication, an incorrect cache-miss-ratio had been displayed in Web Console, and had been returned in response to a cbstats command. We had erroneously incremented ep_bg_fetched for GET_META background fetches. As a fix, we now provide a separate stat for GET_META background fetches.

    Issues : MB-6628

  • Get-and-touch returned incorrect error messages when an error occurs. Get-and-touch now returns ENOENT if key does not exist.

    Issues : MB-6840

  • This enables users to change the disk location of an index without destroying persisted data. You can now set index_path and it will delete an existing index only and create a new disk location for use.

    Issues : MB-6423

  • When you try to automatically failover a node, Couchbase Server will not perform the failover if there are not enough replica vBuckets in the cluster to support the failed node.

    Issues : MB-6209

  • Querying a view during rebalance had resulted in several errors due to the way database storage files were managed and named. We now exclude opening databases that are meant to be excluded from indexing and we now synchronously open databases for indexing to resolve the problem.

    Issues : MB-6612

  • Querying a view on a single node incorrectly returned inconsistent_state error if a bucket is empty. This is corrected.

    Issues : MB-6736

  • Provide additional XDCR information on Logs tab of Couchbase Web Console.

    Issues : MB-6888

  • We added missing checks to state transition requests. Also erroneous error messages had occurred while the server monitored partition in pending transition. This has been corrected.

    Issues : MB-6490

  • The collect_info logs was missing the mapreduce_errors log file. Now this log also contains mapreduce_errors.

    Issues : MB-6859

  • Change the frequency that internal timeouts on Windows were occurring to be more efficient.

    Issues : MB-6653

  • Node rebalance was failing when new nodes were added to the cluster. This occurred due to processes being triggered after defining partitions for indexing. The processes are now being triggered at the correct time.

    Issues : MB-6706

  • Replication had exited with replicator_died message after multiple attempts to update. Problem was caused by using old revision numbers for new database files. Now new database files use new revision numbers, resolving the problem.

    Issues : MB-6711

  • Sporadic failures occurred while running a unit test for testing duplicate items on disk. Test now modified to use less items.

    Issues : MB-6647

  • Keys stored in the access log were not correctly scheduled to load, due to a broken logic for detecting duplicate items. Now keys properly load during warmup from access log.

    Issues : MB-6616

  • Couchbase Server had returned a HTTP 404 error when a node is rebalanced and a client tried to cache a list of nodes for a bucket. Now the server sends a HTTP 302 redirect with the URL of an available node.

    Issues : MB-6922

  • The thread responsible for persisting data in Couchbase Server had been crashing during vBucket state changes. This was caused by not handling file not found exceptions. The cause of the crashes has been fixed.

    Issues : MB-6676

  • Check-and-set value was not returned in response to a successful delete request. Now it is returned as part of the response.

    Issues : MB-6661

• Cluster Operations

  • Server now releases returned document that is being marked deleted. This fixes a rebalance failure where memcached crashes on one of the nodes and rebalance exits with the error: {mover_failed,{badmatch, known macro: {error,closed}}}.

    Issues : MB-6806

  • The Couchbase REST API has changed to enable you to change the default maximum number of buckets used in a Couchbase cluster. The maximum allowed buckets in this request is 128, however the maximum suggested number of buckets is ten per cluster. This is a safety mechanism to ensure that a cluster does not have resource and CPU overuse due to too many buckets. The following illustrates the endpoint and parameters used:

    shell>    curl -X -u admin:password -d maxBucketCount=6 http://ip_address:8091/internalSettings
    

    For this request you need to provide administrative credentials for the cluster. The following HTTP request will be sent:

    About to connect() to 127.0.0.1 port 8091 (#0)
       Trying 127.0.0.1…
       connected
       Connected to 127.0.0.1 (127.0.0.1) port 8091 (#0)
       Server auth using Basic with user ‘Administrator’
       POST /internalSettings HTTP/1.1
    

    If Couchbase Server successfully changes the bucket limit for the cluster, you will get a HTTP 200 response:

    HTTP/1.1 200 OK
       Server: Couchbase Server 2.0.0r_501_gb614829
       Pragma: no-cache
       Date: Wed, 31 Oct 2012 21:21:48 GMT
       Content-Type: application/json
       Content-Length: 2
       Cache-Control: no-cache
    

    If you provide an invalid number, such as 0, a negative number, or an amount over 128 buckets, you will get this error message:

    ["Unexpected server error, request logged."]
    

    For more information about setting buckets per cluster via REST API, see Setting Maximum Buckets for Clusters.

    Issues : MB-5684

    • Automatically prevent a user from creating more than the maximum number of supported buckets in a Couchbase cluster. The default maximum is six.

      Issues : MB-5684

• Web Console

  • Provide cleaner, simplified output on error messages from XDCR replication.

    Issues : MB-6763

• Command-line Tools

  • Incorrect message had been sent in response to a cbstats vkey command. Server had returned the string ‘not found’ for valid request. Now correct the memcached protocol error is returned. For more information about cbstats, see cbstats Tool.

    Issues : MB-6751

  • Fixed stats vkey status for evicted keys. Stats vkey was returning item_deleted instead of valid for evicted keys. This change fixes that problem.

    Issues : MB-6840

  • cbepctl help options now show option for setting the expiry_pager, a maintenance process for removing deleted items from disk.

    Issues : MB-6764

• Indexing and Querying

  • Remove an internal setting dialog used internally by Couchbase for testing consistent views.

    Issues : MB-6713

  • On Window platform, errors occurred trying to update a design document. This is now fixed.

    Issues : MB-6653

  • When consistent views were enabled and rebalance was being performed, the rebalance would fail. This was due to incorrect handling of empty partitions and by accidentally performing disk cleaning before updating partitions which would not be indexed. This is fixed.

    Issues : MB-6612

• Cross Datacenter Replication (XDCR)

  • In the past we had displayed several confusing error messages and warnings for XDCR. We had provided low level information in the Couchbase Web Console that is now provided to low files to avoid overwhelming users with information. We were also reporting errors that were actually more appropriately called warnings since they were recoverable issues. We have changed those errors to warning/advisories.

    Issues : MB-6934

  • By default, the server automatically disables flushing data from a source data bucket when XDCR replications exist for that bucket.

    Issues : MB-6809

  • Renamed “XDCR replication queue” in summary section to “XDCR docs to replicate” for clarity.

    Issues : MB-6924

  • Replication via XDCR had experienced performance degradation when a data bucket contained a higher ratio of expired items. This has been fixed by ignoring the expiration time set for an item, SET_WITH_META.

    Issues : MB-6662

  • We have added 3 new outbound operation stats, namely, 1) data replicated, which is amount of data XDCR have replicated to the remote data center through inter- cluster network; 2) active vb replications, which shows the number of ongoing active replications to the remote clusters; 3) waiting vb replications, which is the number of vb replications in the waiting pool to wait for turn to start replication. These stats will be useful for performance monitoring and diagnosis.

    Issues : MB-6919

  • Couchbase Server was dropping connections from client libraries too quickly when a node in a cluster was being rebalanced. Now there will be more delay until a connection is dropped.

    Issues : MB-5406

  • By default, the server automatically disables flushing data from a source data bucket when XDCR replications exist for that bucket.

    Issues : MB-6809

• Performance

  • Increase maximum number of retries to open the database file.

    Issues : MB-6844

  • Prioritize flushing pending vbuckets over regular vbuckets. This is a performance improvement used for rebalancing buckets that have no views or design docs when consistent view mode is enabled.

    Issues : MB-6796

  • Couchbase Server had experienced a one second delay to mark empty and closed checkpoints on a persistence queue. Performance improvements made to eliminate delay.

    Issues : MB-6714

Known Issues in 2.0.0 build #1870

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

Release Notes for Couchbase Server 2.0.0 Beta (18 September 2012)¶

This is the Beta release of Couchbase Server 2.0. Couchbase Server 2.0 is the next major version of Couchbase Server. The 2.0 version adds support for distributed indexing and query, real-time map/reduce functions and cross-data center replication. Couchbase Server 2.0 builds on the high performance Simple, Fast, and Elastic Couchbase Server 1.8. The beta release is available to all enterprise- and community-edition customers. For more information about Couchbase Server 2.0, visit Couchbase Server 2.0.

New Features and Behavior Changes in 2.0.0

• Two sample databases can be loaded either during setup or in the setting panel.

• Advanced indexing configuration can be updated in the Couchbase Admin console including maximum number of index building tasks that are executed in parallel.

• Design documents for active data are automatically indexed when a threshold on time is met or a number of document mutations is reached. This is user configurable.

  For more information, see Automated Index Updates.

• New statistics have been added to understand the cross data center replication streams. The source cluster will show information about each XDCR including document mutation to be replicated.

  For more information, see Viewing Bucket and Cluster Statistics.

• Backup and Restore support is now available.

  For more information, see Backup and Restore.

• Debug information has been added into the view and indexing operations to make debugging views easier. You can enable this by using debug=true as query parameter.

• E-mail alerts can now be created when certain error situations are encountered in a cluster.

  For more information, see Enabling Alerts.

• You can now manually compact data and design documents using the admin console.

  For more information, see Using the Views Editor.

Fixes in 2.0.0

• Database Operations

  • Provide return value of ‘not found’ in response to get operations on document that does not exist.

  • Enable sending compression option as parameter for a document to Couchbase Server.

    Issues : MB-6482

• Cluster Operations

  • Fixed incorrect message, ‘There are currently no documents in this bucket.’ to ‘there are currently no documents in this bucket corresponding to the search criteria.’

    Issues : MB-6442

  • Fixed rebalance failure. Rebalanced had stalled after performing failover and removing node due to memory leak on cluster nodes.

    Issues : MB-6550

• Web Console

  • Fix Couchbase Admin Console layout when a design document or view has a long name.

    Issues : MB-5465

  • Corrected intermittent failures occurred when loading sample data via setup wizard or the Settings tab on MAC when user starts couchbase server app for the first time. Occurred due to some permission issues.

    Issues : MB-6452

  • Corrected wrong build number displayed in Mac OS X builds in dialog box.

    Issues : MB-6668

  • Fix Couchbase Admin Console behavior when failover is in progress and node goes offline.

    Issues : MB-4756

• Command-line Tools

  • Restore connection to hostname instead of IP address.

    Issues : MB-6470

• Indexing and Querying

  • Compaction file for views had been deleted if the process for index compaction died.

  • Deleting design documents in development resulted in deleting production index files.

    Issues : MB-6517

• Cross Datacenter Replication (XDCR)

  • Fix rebalance timeout failure during unidirectional replication of items via XDCR. Failure had returned message: “timeout, ns_memcached-bucket',‘ns_1@10.1.3.238’}, {get_vbucket,”.

    Issues : MB-6493

  • Provide REST API endpoint for cancelling replication request.

    Issues : MB-6381

Known Issues in 2.0.0

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • An upgrade path is not supported to the beta release from prior developer preview builds. You need to uninstall your developer preview release and install the new release.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Database Operations

  • In rare cases codes used to test for data corruption (CRC, checksum) codes do not match when reading data from couch file.

    Issues : MB-6538

  • Bucket deletion fails to delete on-disk data and indexes during indexing and data compaction.

    Issues : MB-6382

• Cluster Operations

  • Rebalance fails with error “bulk_set_vbucket_state_failed” due to timeout in tap_replication_manager for default bucket.

    Issues : MB-6595

  • One of the internal maintenance processes within Couchbase Server for checking vBuckets will stop node rebalance when you create replication via XDCR on a source cluster.

    A node in a cluster may also stop rebalance when another node orchestrating rebalances is over loaded. When a node stops rebalance, it results in the error message “Resetting rebalance status since it is not really running”.

    Rebalance cna also fail due to the timeout in bulk_set_vbucket_state operation with continuous view queries.

    Issues : MB-6481, MB-6573, MB-7212

  • Microsoft Windows 7: when you create a bucket immediately after another bucket is deleted, Couchbase Server may timeout.

    Issues : MB-6664

  • memcached hangs when aborting during swap rebalance operation and fails to restart ( exit 71 ).

    Issues : MB-6592

• Web Console

  • The Couchbase Admin console needs to handle a very slow docloader. Alternatively, docloader may be too slow.

    Issues : MB-5938

  • Preview Random Document in the View tab does not show the actual values for document revision, expiration, flags.

    Issues : MB-6620

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

• Indexing and Querying

  • Development indexes will remain on disk after bucket deletion.

    Issues : MB-6366

  • Accessing a recently created view (with other, existing active views) may return a error if the corresponding design document and view definition have not been replicated across the cluster. The error return will be returned in error of the view output detailing the missing design document. The workaround is to add views and design documents to your node or cluster after you have performed rebalance. For more information about resolving issues with Couchbase Views, see Troubleshooting Views (Technical Background).

    Note also that stopping a rebalance operation on a cluster may take a long time if compaction and indexing operations are in progress on the cluster at the point of rebalance. Again, the workaround is to add views and index and query views after you have performed compaction or rebalance. For more information about rebalance, and considerations on when to rebalance, see Rebalancing.

    Issues : MB-6726, MB-6339

  • If a cluster is being rebalanced, and a node does not yet have any active vBuckets, you will receive the error "error":"no_active_vbuckets" when you query a view via the REST API.

    Issues : MB-6633

  • Indexing 11 design documents at once will significantly reduce Couchbase Server response times.

    Issues : MB-6392

• Cross Datacenter Replication (XDCR)

  • beam.smp memory usage grows to 2 GB when XDCR feature is enabled and rebalancing is in progress.

    Issues : MB-6649

  • Very inconsistent statistics may occur with bi-directional XDCR when running with a moderate/low load.

    Issues : MB-6598

  • Replication rat e may drop when the XDCR replication queue size becomes less than 500 items.

    Issues : MB-6586

  • You may experience very slow replication rates (less than 100 items on average per second) with 2 unidirectional replications between 2 clusters.

    Issues : MB-6643

• Performance

  • Mac OS X startup time for restart is quite long considering the number of items.

    Issues : MB-6613

  • ep-engine needs 1.5 minutes to create 1024 vbuckets. This may be too slow, however performance improves with setting barrier=0.

    Issues : MB-6232

Release Notes for Couchbase Server 2.0.0 Build #1672 Developer Preview (10 September 2012)¶

New Features and Behavior Changes in 2.0.0 Build #1672

• New statistics have been added to understand the cross data center replication streams. The source cluster will show information about each XDCR including document mutation to be replicated.

  For more information, see Viewing Bucket and Cluster Statistics.

Fixes in 2.0.0 Build #1672

• Database Operations

  • Use the mutation log compactor sleep time from the configuration

  • Check each vbucket’s bg queue to set the task sleep time

    Issues : MB-6215

  • Only one access scanner should be scheduled at any time

    Issues : MB-6211

  • Refactor add_with_meta test function

    Issues : MB-100

  • Update access scanner run counter when it is completed.

    Issues : MB-6194

  • Requeue failed bgfetch requests for retry

    Issues : MB-6222

  • Disable access scanner scheduling at a specific time

    Issues : MB-6057

  • Reset checkpoint cursors after receiving backfill streams

    Issues : MB-6084

  • Remove the mutation log if exists at the end of each test runs

  • expose TAP_FLAG_TAP_FIX_FLAG_BYTEORDER to python

    Issues : MB-6176

  • return TMPFAIL for failed bgfetch instead of assert

    Issues : MB-6323

• Cluster Operations

  • Fixed iterate_ddocs return values

    Issues : MB-5307

  • Replication stats on UI

    Issues : MB-5943

  • Faster xdcr startup by using cached remote cluster info

    Issues : MB-100

  • Add logs to time replication stop

    Issues : MB-6041

  • Send out email alerts asynchronously.

    Issues : MB-6131

  • Don’t send web alerts emails when they are disabled.

    Issues : MB-5307

  • Added cancel bucket compaction button

    Issues : CBD-181

  • Periodically update replica indexes.

    Issues : MB-6269

  • Restart view compaction when getting shutdown errors.

    Issues : MB-6342

  • Expose xdcr replications via tasks API

    Issues : MB-6381

  • Maintain and collect XDCR vb stats

    Issues : MB-5943

  • Added false/true options for reduce

    Issues : MB-6149

  • REST API to alter set view update daemon parameters

    Issues : CBD-423

  • REST API to update per ddoc updateMinChanges.

    Issues : CBD-423

  • Don’t shutdown bucket unless we’re deleting it

    Issues : MB-6384

  • Use optimized math for cache miss rate

    Issues : MB-6403

  • Add compaction_daemon settings to config on upgrade.

    Issues : MB-5307

  • More efficient index state computation

    Issues : CBD-546

  • Allow sending web alerts via email.

    Issues : MB-6131

  • Sort ddocs by id on ddocs endpoint

    Issues : MB-5307

  • Inform user whether swap rebalance happens

    Issues : MB-6162

  • Move email helpers from ns_mail_log to ns_mail.

    Issues : MB-6131

  • Enabled emails for all alerts by default

    Issues : MB-6131

  • Implemented replication cancellation endpoint

    Issues : MB-6381

  • Fixed saving map/reduce functions into wrong views

    Issues : MB-6167

  • Bump up default MAX_CONCURRENT_REPS_PER_DOC to 32

    Issues : CBD-399

  • Started new REST api docs

    Issues : MB-5307

• Indexing and Querying

  • Fix too high memory consumption during indexing

    Issues : MB-6096

  • Ignore index pausing of already paused partitions

    Issues : MB-6165

  • More explicit error message when keys are too long

    Issues : MB-6295

  • Delete index files on terminate after ddoc updated

    Issues : MB-6415

  • Delete compaction file if index compactor dies

    Issues : MB-100

  • Delete index files on view group terminate

    Issues : MB-6415

Known Issues in 2.0.0 Build #1672

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

• Indexing and Querying

  • Accessing a recently created view (with other, existing active views) may return a error if the corresponding design document and view definition have not been replicated across the cluster. The error return will be returned in error of the view output detailing the missing design document. The workaround is to add views and design documents to your node or cluster after you have performed rebalance. For more information about resolving issues with Couchbase Views, see Troubleshooting Views (Technical Background).

    Note also that stopping a rebalance operation on a cluster may take a long time if compaction and indexing operations are in progress on the cluster at the point of rebalance. Again, the workaround is to add views and index and query views after you have performed compaction or rebalance. For more information about rebalance, and considerations on when to rebalance, see Rebalancing.

    Issues : MB-6726, MB-6339

Release Notes for Couchbase Server 2.0.0 Build #1554 Developer Preview (10 August 2012)¶

Couchbase Server 2.0.0 build 1530 contains important document behavior changes that may impact your existing applications. Specifically, this and future releases include changes the way document metadata is handled and exposed when working with Views and creating map and reduce functions in Couchbase Server.

In previous releases, the document supplied as the only argument to the map() function included special fields with an additional prefix that provided information such as the data type, flags, expiration and document ID. For example:

{
 "_id" : "contact_475",
 "_rev" : "1-AB9087AD0977F089",
 "_bin" : "...",
 "$flags" : 0,
 "$expiration" : 0,
 "name" : "Fred Bloggs",
}

This representation has been changed so that the submitted document data and structure remain identical to the document stored and returned by the Views system.

The metadata is now supplied as a object and second argument to the map() function. The format of this object is a JSON document with fields for each of the metadata items previously incorporated in the main document. For example:

{
 "id" : "contact_475",
 "rev" : "1-AB9087AD0977F089",
 "flags" : 0,
 "expiration" : 0,
 "type" : "json",
}

The main flags and their contents remain the same. The _bin, $att_reason have been replaced with a single field, type, that indicates the document data type. For documents identified as valid JSON, the field will have the value json. For non-JSON, the value will be base64.

The meta information for sample documents is now displayed separately, within a non-editable portion of the Web Console.

In addition to these changes, the format and information supplied to the map() function has changed.

To access only the document data within your View, you can use the following map() :

function(doc) {
}

To access the document data and document metadata, including document ID and expiration time, use the two-argument format of the function:

function(doc,meta) {
}

For example, to emit only document information from the View based on the following document structure:

{
 "name": "John",
 "e-mail": "john@john.com"
}

Create a view using only the document object:

function (doc) {
 emit(doc.name,null);
}

To create a view that explicitly emits the document ID:

function (doc,meta) {
 emit(meta.id,doc.name);
}

In addition, the doc argument now contains a base64 representation of the document data if the document is not JSON. This can identified using the type field of the meta object. The default map() provided within the Administration Web Console is now:

function (doc, meta) {
 if (meta.type == "json") {
 // If the document is JSON, sort by the schema
 var keys = Object.keys(doc);
 emit(["json", keys.length], keys);
 } else {
 emit(["blob"]);
 }
}

This provides an example of how to process and output documents that are valid JSON or binary documents, using the meta argument to identify the document data type.

Existing client libraries continue to work with the new release without modification to the View or document update mechanisms and information.

New Features and Behavior Changes in 2.0.0 Build #1554

• Behavior Change: Identifying the content type of the document can no longer be achieved by using the doc._bin field of the document object. Instead, you should use the meta.type field. This will be set to json for documents identified as valid JSON documents. For documents that cannot be identified as valid JSON, the field will be set to base64.

  For more information, see Document Metadata.

• Behavior Change: Document metadata is no longer included as fields within the document supplied to the map() function as an argument within a view. Instead, the function is now supplied two arguments, the document data, and a second argument, meta, that contains the expiration, flags and an indication of the document data type.

  For more information, see Document Metadata.

• Behavior Change: The document ID for a given document is no longer available within the document object supplied to the map(). Instead of using doc._id you should now use the id field of the meta object, meta.id. The two-argument form of the map() must be used for this purpose.

  For more information, see Map Functions.

• Behavior Change: Because document metadata is now exposed within a separate structure, the Admin Console displays the sample document metadata separately from the main document content.

  For more information, see Using the Views Editor.

• Behavior Change: When deleting a design document, the _rev parameter is no longer required to confirm the deletion.

  For more information, see Design Document REST API.

• Behavior Change: The map() is now supplied two arguments, doc, which contains the document data, and meta, which contains the document metadata.

  For more information, see Map Functions.

Known Issues in 2.0.0 Build #1554

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

• Indexing and Querying

  • Accessing a recently created view (with other, existing active views) may return a error if the corresponding design document and view definition have not been replicated across the cluster. The error return will be returned in error of the view output detailing the missing design document. The workaround is to add views and design documents to your node or cluster after you have performed rebalance. For more information about resolving issues with Couchbase Views, see Troubleshooting Views (Technical Background).

    Note also that stopping a rebalance operation on a cluster may take a long time if compaction and indexing operations are in progress on the cluster at the point of rebalance. Again, the workaround is to add views and index and query views after you have performed compaction or rebalance. For more information about rebalance, and considerations on when to rebalance, see Rebalancing.

    Issues : MB-6726, MB-6339

Release Notes for Couchbase Server 2.0.0 Build #1495 Developer Preview (26 July 2012)¶

Couchbase Server 2.0.0 build 1495 introduces important changes with respect to accesing views from buckets that have been secure with SASL authentication.

To access a view from a bucket with SASL authentication through the REST API you must supply the bucket name and password as the username and password to the URL of the HTTP request. For example:

GET http://bucketname:bucketpass@localhost:8092/bucketname/_design/designdocname/_view/viewname

Failure to provide the authentication information on a secure bucket will result in an HTTP error response (401).

For more information, see Querying Using the REST API.

The same rules also apply to creating and reading design documents using the REST API.

For more information, see Design Document REST API.

Known Issues in 2.0.0 Build #1495

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

• Indexing and Querying

  • Accessing a recently created view (with other, existing active views) may return a error if the corresponding design document and view definition have not been replicated across the cluster. The error return will be returned in error of the view output detailing the missing design document. The workaround is to add views and design documents to your node or cluster after you have performed rebalance. For more information about resolving issues with Couchbase Views, see Troubleshooting Views (Technical Background).

    Note also that stopping a rebalance operation on a cluster may take a long time if compaction and indexing operations are in progress on the cluster at the point of rebalance. Again, the workaround is to add views and index and query views after you have performed compaction or rebalance. For more information about rebalance, and considerations on when to rebalance, see Rebalancing.

    Issues : MB-6726, MB-6339

Release Notes for Couchbase Server 2.0.0DP4 Developer Preview (21 March 2012)¶

Couchbase Server 2.0.0 Developer Preview 4 contains a number of new features and functionality.

What’s new in this release

• Replica Indexes

  The indexes generated by the map/reduce view interface are replicated across the cluster. This ensures that if there is a failover scenario, the index information does not have to be regenerated by the replacement node.

• Experimental Geospatial Indexing

  Support has been added for supporting geospatial indexing and querying. The geospatial interface enables the storage of two-dimensional geometry points. Views can then be written that index this information, and queries can be written that return the geospatial information based on the provision of a bounding-box to the geometry data.

  For more information, see Writing Geospatial Views.

• Sample Databases

  Couchbase Server now includes sample databases as part of the installation and setup process. You can load the sample data and associated views. This provides both the sample data structures and map/reduce queries to enable youf to understand and create your own datasets and views.

  For more information, see Couchbase Sample Buckets.

New Features and Behavior Changes in 2.0.0DP4

• The index/view related improvements are for production views or development views with full_set=true.

• The indexes created by the view system are now replicated among nodes to ensure that indexes do not need to be rebuilt in the event of a failover.

• A new option, on_error has been added to control the behavior of the view engine when returning a request. By default the value is continue, which indicates that the view engine should continue to return results in the event of an error. You can also set the option to stop to stop the view results being returned on failure.

  For more information, see Error Control.

  Tags : views

• The view system has been stabilised to work even while the cluster topology is changing through rebalance and failover operations.

• The design document and view system has been updated with the ability to create multiple design docs and query all these design docs in parallel.

• Experimental support for geospatial indexing has been added.

  For more information, see Writing Geospatial Views.

  Tags : experimental, geospatial

• You now have the option to have sample data (and views) created during the installation and setup process. This operation requires Python 2.6.

  For more information, see Couchbase Sample Buckets.

• A number of stability bugs have been fixed when querying and merging views.

• The default value of the stale argument when querying views has been changed to update_after. This means that by default view information will always be returned ‘stale’, and updated after the view request has completed.

  You can force a view update by specifying false to the stale, or ok to enable stale views without an implied update after the view data has been returned.

  For more information, see Querying Views.

  Tags : views

• Support for changing (and accessing) the number of parallel indexing processes used to build the view index information has been added to the Couchbase Management REST API.

  For more information, see Setting Maximum Parallel Indexers.

  Tags : restapi, views

Fixes in 2.0.0DP4

• Cluster Operations

  • Rebalancing in a new Couchbase Server 1.8 node if there are less than 500,000 items results in an imbalanced cluster.

    Issues : MB-4595

  • When upgrading from Couchbase Server 1.8.0 to 1.8.1 or Couchbase Server 1.8.0 to 2.0, an offline upgrade may fail with a rebalance failure reporting the error {wait_for_memcached_failed,"bucket-1"}.

    Issues : MB-5532

• Unclassified

  • The web console UI had an incorrect query parameter, start_key_docid available for selection. This should have been start_key_doc_id.

    Issues : MB-4781

  • When deleting a bucket, and then creating a new bucket with the same name, the views associated with the deleted bucket would reappear.

    Issues : MB-4562

  • The ep-engine component did not persist the mutated replica items to disk.

    Issues : MB-4629

  • The number of threads started when building indexes could increase to an unmanageable level causing a significant performance problem. The indexing system has been configured so that the main indexers get 4 exclusive slots, and the replica index builders 2 exclusive slots to ensure that the indexing process proceeds effectively.

    Issues : MB-4848

  • Accessing a view query would fail if the user changes a design document while a rebalance was occurring, and then accesses the updated view.

    Issues : MB-4626

  • Accessing a view using a reduce could report different counts from different nodes after a cluster has been rebalanced with the addition of new nodes.

    Issues : MB-4500

  • Querying a view when deleting items and performing a rebalance simultaneous leads to invalid results.

    Issues : MB-4518

  • The ns_server process could crash on Linux because of too many open file descriptors if more than 10 views were defined on a single bucket.

    Issues : MB-4514

  • Creating a view with a reduce function, and querying while changing the cluster topology through a rebalance could cause incorrect results.

    Issues : MB-4692

  • Accessing the timings statistics through the cbstats command would fail.

    Issues : MB-4718

  • The compaction process on a node can be terminated while data is still being loaded, but fail to restarted again while the node is still under load.

    Issues : MB-4732, MB-4774

  • If you remove and rebalance a node out of a running cluster while clients are awaiting view results from that node, the node would fail to be rebalanced properly.

    Issues : MB-4752

  • An incorrect total cluster storage figure could be reported if the index_path and data_path configurations are on the same disk.

    Issues : MB-4512

  • When accessing information using the basic create, read, update or delete operations, the $flags and $expiration flags are returned through the HTTP API for individual documents. This matches the output available through the view API when including the entire document.

    Issues : MB-4549

Known Issues in 2.0.0DP4

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

• Indexing and Querying

  • Accessing a recently created view (with other, existing active views) may return a error if the corresponding design document and view definition have not been replicated across the cluster. The error return will be returned in error of the view output detailing the missing design document. The workaround is to add views and design documents to your node or cluster after you have performed rebalance. For more information about resolving issues with Couchbase Views, see Troubleshooting Views (Technical Background).

    Note also that stopping a rebalance operation on a cluster may take a long time if compaction and indexing operations are in progress on the cluster at the point of rebalance. Again, the workaround is to add views and index and query views after you have performed compaction or rebalance. For more information about rebalance, and considerations on when to rebalance, see Rebalancing.

    Issues : MB-6726, MB-6339

• Unclassified

  • The default bucket may be shutdown unexpectedly when accessing multiple views using the test script environment.

    Issues : MB-4940 ; Tags : windows

  • Because of the way information is stored within the cluster, persisted to disk, and views are updated, it is possible to store a value into the cluster and be unable to immediately retrieve that value through a corresponding view.

    Tags : views

    For more information, see Document Storage and Indexing Sequence.

  • A rebalance on Windows may fail when adding a new node to the cluster with the error {wait_for_memcached_failed,"bucket-9"} on a cluster configured with 10 buckets.

    Issues : MB-4849 ; Tags : windows

  • Couchbase Server can fail when adding a failed over node back into a cluster during a rebalance operation with the error:

    Core was generated by `/opt/couchbase/bin/memcached -X /opt/couchbase/lib/memcached/stdin_term_handler'.
     Program terminated with signal 11, Segmentation fault.
     #0 LoadStorageKVPairCallback::callback (this=0xb9dd8c0, val=…) at stored-value.hh:168
     in stored-value.hh
    

    Workaround : Reinstall Couchbase Server on the node that failed before adding the node back and performing the rebalance.

    Issues : MB-4959

    • Rebalance may fail because memcached is closing the connection during the authentication request.

      Issues : MB-4824

    • A rebalance when removing a single node from an existing cluster can fail on Windows with the error wait_for_memcached_failed,"default".

      Issues : MB-4890 ; Tags : windows

    • View queries return “inconsistent state” error if user calls the flush operation.

      Issues : MB-4717,

    • The disk write queue can become high and very slow to drain if user is running view queries on a large number of design docs simultaneously, with compaction and index still in progress.

      Issues : MB-4846

    • Couchbase Server may fail to restart properly after having been shutdown.

      Issues : MB-4933 ; Tags : windows

    • Querying views when new nodes are added and not rebalanced into the cluster, with another node failed over generate an error:

      {
        "error":"error",
        "reason":"A view spec can not consist of merges exclusively."
       }
      

      Issues : MB-4804

    • The Couchbase sample bucket loader scripts require Python 2.6 as the default version of Python installed. If Python is installed, but the default is not Python 2.6 the sample bucket loader script will fail.

      Workaround : You can install Python 2.6 and then create a link between /usr/bin/python to point to the installed /usr/bin/python2.6.

      Issues : MB-4724

    • Disk usage can grow because compaction does not run until the indexing process has finished. In a system with a high number of design docs, the indexing takes too long.

      Issues : MB-4849

Release Notes for Couchbase Server 2.0.0DP3 Developer Preview (13 December 2011)¶

This is the 3rd ‘developer preview’ edition of Couchbase Server 2.0.

New Features and Behavior Changes in 2.0.0DP3

• Status bars have been added to show view building and rebalance progress.

• The admin Web Console includes a document viewing and editing interface.

  For more information, see Using the Document Editor.

• The Couch API REST port has been changed from 5984 to 8092. Applications using 5984 for view creation and basic create, read, update, and delete operations need to be updated to use the updated port.

  Tags : important, incompatible, network

• Major performance and stability improvements when merging views across multiple nodes.

• Major performance improvements when writing and persisting data to disk from memory.

Fixes in 2.0.0DP3

• Unclassified

  • Couchbase Server would fail to start on Windows Server 2008 64-bit platform.

    Issues : MB-4380 ; Tags : installer, windows

  • During the warm-up process when the server is first starting and loading items, ep-engine could fail with an assertion error.

    Issues : MB-4513

  • Querying a view when deleting items and performing a rebalance simultaneous leads to invalid results.

    Issues : MB-4518

  • memcached could crash while rebalancing a large number of nodes with a very high number of items.

    Issues : MB-4394

  • When running the view tests on Windows, Couchbase Server could hang and fail to return any values.

    Issues : MB-4515

  • The resident ratio of items could report a negative number of items.

    Issues : MB-4340

  • The JSON encoding system within the view indexing module could over escape double quotes within embedded values.

    Issues : MB-4511

Known Issues in 2.0.0DP3

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

• Unclassified

  • Querying a view when deleting items and performing a rebalance simultaneous leads to invalid results.

    Issues : MB-4518

  • View queries return “inconsistent state” error after a failover and rebalance operation.

    Issues :

  • Rebalancing can cause memcached to fail with error status 255.

    Issues :

  • Query results from views may be incorrect when the topology of the cluster changes.

  • It is not possible up create a bucket with uppercase letters in the bucket name.

    Issues : MB-4265

  • Accessing a view using a reduce could report different counts from different nodes after a cluster has been rebalanced with the addition of new nodes.

    Issues : MB-4500

Release Notes for Couchbase Server 2.0.0DP2 Developer Preview (23 August 2011)¶

This is the 2nd ‘developer preview’ edition of Couchbase Server 2.0.

Known Issues in 2.0.0DP2

• Installation and Upgrade

  • It is not possible to perform an upgrade between Couchbase Server 2.0 pre-releases including beta, or to perform an offline upgrade from Couchbase Server 1.8 to a pre-release or beta of Couchbase Server 2.0. To upgrade between these versions use cbbackup to backup your data, delete the existing installation, install the new version, and restore the stored data.

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

  • Documents identified as Non-JSON stored within Couchbase Server may appear as binary, or text-encoded binary data within the UI.

    Issues : MB-7069

  • During periods of moderate CPU load on the Couchbase Server cluster, you may see warnings that IP address seems to have changed. Unable to listen to node X.X.X.X.

    Issues : MB-7115, MB-7238, MB-7228

• Command-line Tools

  • The cbbackup, cbrestore, and cbtransfer command-line tools require the zlib module for Python to have been installed. If Python was installed from source, you must have enabled zlib using the --with-zlib option during the build process.

    Issues : MB-7256

    For more information, see Backup and Restore, Uninstalling Couchbase Server.

Release Notes for Couchbase Server 2.0.0DP Developer Preview (29 July 2011)¶

This is the 1st ‘developer preview’ edition of Couchbase Server 2.0.