rebalance

    +

    Rebalances data and indexes across nodes in a cluster

    SYNOPSIS

    couchbase-cli rebalance [--cluster <url>] [--username <user>] [--password <password>]
        [--client-cert <path>] [--client-cert-password <password>] [--client-key <path>]
        [--client-key-password <password>] [--server-remove <servers>] [--no-progress-bar]
        [--no-wait]

    DESCRIPTION

    Rebalances data and indexes across all nodes in the cluster. This command should be used after nodes are added, removed, or failed over from the cluster in order to ensure that each node in the cluster has a similar "balanced" amount of data and indexes.

    To add nodes use the server-add subcommand. To remove nodes specify the list of nodes to remove using the --server-remove option in the rebalance subcommand. To failover nodes see the failover subcommand. After running the server-add or failover subcommands ensure that you run the rebalance command to balance data and indexes across the cluster.

    OPTIONS

    -c
    --cluster

    Specifies the hostname of a node in the cluster. See the HOST FORMATS section for more information on specifying a hostname.

    -u
    --username <username>

    Specifies the username of the user executing the command. If you do not have a user account with permission to execute the command then it will fail with an unauthorized error.

    -p
    --password <password>

    Specifies the password of the user executing the command. If you do not have a user account with permission to execute the command then it will fail with an unauthorized error. If this argument is specified, but no password is given then the command will prompt the user for a password through non-echoed stdin. You may also specify your password by using the environment variable CB_REST_PASSWORD.

    --client-cert <path>

    The path to a client certificate used to authenticate when connecting to a cluster. May be supplied with --client-key as an alternative to the --username and --password flags. See the CERTIFICATE AUTHENTICATION section for more information.

    --client-cert-password <password>

    The password for the certificate provided to the --client-cert flag, when using this flag, the certificate/key pair is expected to be in the PKCS#12 format. See the CERTIFICATE AUTHENTICATION section for more information.

    --client-key <path>

    The path to the client private key whose public key is contained in the certificate provided to the --client-cert flag. May be supplied with --client-cert as an alternative to the --username and --password flags. See the CERTIFICATE AUTHENTICATION section for more information.

    --client-key-password <password>

    The password for the key provided to the --client-key flag, when using this flag, the key is expected to be in the PKCS#8 format. See the CERTIFICATE AUTHENTICATION section for more information.

    --server-remove <servers>

    A comma separated list of nodes to remove from the cluster. Each node in the list should correspond to the hostname or IP address of that server.

    --no-progress-bar

    Hides the progress bar which tracks the progress of the rebalance. This command will still wait for rebalance completion even if this flag is specified, but the progress bar will not be shown.

    --no-wait

    Specifies that this command should not wait for the completion of rebalance before exiting.

    HOST FORMATS

    When specifying a host for the couchbase-cli command the following formats are expected:

    • couchbase://<addr>

    • <addr>:<port>

    • http://<addr>:<port>

    It is recommended to use the couchbase://<addr> format for standard installations. The other two formats allow an option to take a port number which is needed for non-default installations where the admin port has been set up on a port other that 8091.

    CERTIFICATE AUTHENTICATION (MTLS AUTHENTICATION)

    This tool supports authenticating against a Couchbase Cluster by using certificate based authentication (mTLS authentication). To use certificate based authentication a certificate/key must be supplied, there a currently multiple ways this may be done.

    PEM ENCODED CERTIFICATE/KEY

    An unencrypted PEM encoded certificate/key may be supplied by using: - --client-cert <path> - --client-key <path>

    The file passed to --client-cert must contain the client certificate, and an optional chain required to authenticate the client certificate.

    The file passed to --client-key must contain at most one private key, the key can be in one of the following formats: - PKCS#1 - PKCS#8

    Currently, only the following key types are supported: - RSA - DSA

    PEM ENCODED CERTIFICATE/PEM OR DER ENCRYPTED PKCS#8 KEY

    An encrypted PKCS#8 formatted key may be provided using: - --client-cert <path> - --client-key <path> - --client-key-password <password>

    The file passed to --client-cert must contain the client certificate, and an optional chain required to authenticate the client certificate.

    Currently, only the following key types are supported: - RSA - DSA

    ENCRYPTED PKCS#12 CERTIFICATE/KEY

    An encrypted PKCS#12 certificate/key may be provided using: - --client-cert <path> - --client-cert-password <password>

    The file passed to --client-cert must contain the client certificate and exactly one private key. It may also contain the chain required to authenticate the client certificate.

    Currently, only the following key types are supported: - RSA - DSA

    EXAMPLES

    To rebalance a new node into the cluster you would first add a node using the server-add command and then start the rebalance with the rebalance command.

    $ couchbase-cli server-add -c 192.168.1.5:8091 --username Administrator \
     --password password --server-add 192.168.1.6:8091 \
     --server-add-username Administrator --server-add-password password
    $ couchbase-cli rebalance -c 192.168.1.5:8091 --username Administrator \
     --password password

    If you just want to remove a node from the cluster and start a rebalance, just run the rebalance command.

    $ couchbase-cli rebalance -c 192.168.1.5:8091 --username Administrator \
     --password password --server-remove 192.168.1.6:8091

    You can remove multiple nodes at once and run the rebalance with the command below. Note that it will be faster overall removing multiple nodes at once as opposed to removing them one at a time.

    $ couchbase-cli rebalance -c 192.168.1.5:8091 --username Administrator \
     --password password --server-remove 192.168.1.6:8091,192.168.1.7:8091

    To add a node and remove another node you need to run the server-add command before starting the rebalance, as shown below.

    $ couchbase-cli server-add -c 192.168.1.5:8091 --username Administrator \
     --password password --server-add 192.168.1.6:8091 \
     --server-add-username Administrator --server-add-password password
    $ couchbase-cli rebalance -c 192.168.1.5:8091 --username Administrator \
     --password password --server-remove 192.168.1.7:8091

    If you add one node to the cluster and remove a node during the same rebalance, Couchbase Server will do a "swap rebalance". This means data and indexes from the node being removed are moved to the one being added. This means the rebalance will only occur between these two nodes as opposed to involving all nodes in the cluster.

    ENVIRONMENT AND CONFIGURATION VARIABLES

    CB_REST_USERNAME

    Specifies the username to use when executing the command. This environment variable allows you to specify a default argument for the -u/--username argument on the command line.

    CB_REST_PASSWORD

    Specifies the password of the user executing the command. This environment variable allows you to specify a default argument for the -p/--password argument on the command line. It also allows the user to ensure that their password are not cached in their command line history.

    CB_CLIENT_CERT

    The path to a client certificate used to authenticate when connecting to a cluster. May be supplied with CB_CLIENT_KEY as an alternative to the CB_USERNAME and CB_PASSWORD variables. See the CERTIFICATE AUTHENTICATION section for more information.

    CB_CLIENT_CERT_PASSWORD

    The password for the certificate provided to the CB_CLIENT_CERT variable, when using this variable, the certificate/key pair is expected to be in the PKCS#12 format. See the CERTIFICATE AUTHENTICATION section for more information.

    CB_CLIENT_KEY

    The path to the client private key whose public key is contained in the certificate provided to the CB_CLIENT_CERT variable. May be supplied with CB_CLIENT_CERT as an alternative to the CB_USERNAME and CB_PASSWORD variables. See the CERTIFICATE AUTHENTICATION section for more information.

    CB_CLIENT_KEY_PASSWORD

    The password for the key provided to the CB_CLIENT_KEY variable, when using this variable, the key is expected to be in the PKCS#8 format. See the CERTIFICATE AUTHENTICATION section for more information.

    COUCHBASE-CLI

    Part of the couchbase-cli suite