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Version: release-0.7

Configure cluster parameters

The KubeBlocks configuration function provides a set of consistent default configuration generation strategies for all the databases running on KubeBlocks and also provides a unified parameter configuration interface to facilitate managing parameter configuration, searching the parameter user guide, and validating parameter effectiveness.

From v0.6.0, KubeBlocks supports both kbcli cluster configure and kbcli cluster edit-config to configure parameters. The difference is that KubeBlocks configures parameters automatically with kbcli cluster configure but kbcli cluster edit-config provides a visualized way for you to edit parameters directly.

View parameter information

View the current configuration file of a cluster.

kbcli cluster describe-config mysql-cluster  

From the meta information, the cluster mysql-cluster has a configuration file named my.cnf.

You can also view the details of this configuration file and parameters.

  • View the details of the current configuration file.

    kbcli cluster describe-config mysql-cluster --show-detail
  • View the parameter description.

    kbcli cluster explain-config mysql-cluster | head -n 20
  • View the user guide of a specified parameter.

    kbcli cluster explain-config mysql-cluster --param=innodb_buffer_pool_size --config-spec=mysql-consensusset-config

    --config-spec is required to specify a configuration template since ApeCloud MySQL currently supports multiple templates. You can run kbcli cluster describe-config mysql-cluster to view the all template names.

    Output
    template meta:
    ConfigSpec: mysql-consensusset-config ComponentName: mysql ClusterName: mysql-cluster

    Configure Constraint:
    Parameter Name: innodb_buffer_pool_size
    Allowed Values: [5242880-18446744073709552000]
    Scope: Global
    Dynamic: false
    Type: integer
    Description: The size in bytes of the memory buffer innodb uses to cache data and indexes of its tables
    • Allowed Values: It defines the valid value range of this parameter.
    • Dynamic: The value of Dynamic in Configure Constraint defines how the parameter configuration takes effect. There are two different configuration strategies based on the effectiveness type of modified parameters, i.e. dynamic and static.
      • When Dynamic is true, it means the effectiveness type of parameters is dynamic and can be configured online.
      • When Dynamic is false, it means the effectiveness type of parameters is static and a pod restarting is required to make the configuration effective.
    • Description: It describes the parameter definition.

Configure parameters

Configure parameters with configure command

The example below takes configuring max_connections and innodb_buffer_pool_size as an example.

  1. View the current values of max_connections and innodb_buffer_pool_size.

    kbcli cluster connect mysql-cluster
    mysql> show variables like '%max_connections%';
    >
    +-----------------+-------+
    | Variable_name | Value |
    +-----------------+-------+
    | max_connections | 167 |
    +-----------------+-------+
    1 row in set (0.04 sec)
    mysql> show variables like '%innodb_buffer_pool_size%';
    >
    +-------------------------+-----------+
    | Variable_name | Value |
    +-------------------------+-----------+
    | innodb_buffer_pool_size | 134217728 |
    +-------------------------+-----------+
    1 row in set (0.00 sec)
  2. Adjust the values of max_connections and innodb_buffer_pool_size.

    kbcli cluster configure mysql-cluster --set=max_connections=600,innodb_buffer_pool_size=512M
    note

    Make sure the value you set is within the Allowed Values of this parameter. If you set a value that does not meet the value range, the system prompts an error. For example,

    kbcli cluster configure mysql-cluster  --set=max_connections=200,innodb_buffer_pool_size=2097152
    error: failed to validate updated config: [failed to cue template render configure: [mysqld.innodb_buffer_pool_size: invalid value 2097152 (out of bound >=5242880):
    343:34
    ]
    ]
  3. Search the status of the parameter configuration.

    Status.Progress shows the overall status of the parameter configuration and Conditions show the details.

    kbcli cluster describe-ops mysql-cluster-reconfiguring-z2wvn -n default
    Output
    Spec:
    Name: mysql-cluster-reconfiguring-z2wvn NameSpace: default Cluster: mysql-cluster Type: Reconfiguring

    Command:
    kbcli cluster configure mysql-cluster --components=mysql --template-name=mysql-consensusset-config --config-file=my.cnf --set innodb_buffer_pool_size=512M --set max_connections=600

    Status:
    Start Time: Mar 13,2023 02:55 UTC+0800
    Completion Time: Mar 13,2023 02:55 UTC+0800
    Duration: 1s
    Status: Succeed
    Progress: 1/1

    Conditions:
    LAST-TRANSITION-TIME TYPE REASON STATUS MESSAGE
    Mar 13,2023 02:55 UTC+0800 Progressing OpsRequestProgressingStarted True Start to process the OpsRequest: mysql-cluster-reconfiguring-z2wvn in Cluster: mysql-cluster
    Mar 13,2023 02:55 UTC+0800 Validated ValidateOpsRequestPassed True OpsRequest: mysql-cluster-reconfiguring-z2wvn is validated
    Mar 13,2023 02:55 UTC+0800 Reconfigure ReconfigureStarted True Start to reconfigure in Cluster: mysql-cluster, Component: mysql
    Mar 13,2023 02:55 UTC+0800 ReconfigureMerged ReconfigureMerged True Reconfiguring in Cluster: mysql-cluster, Component: mysql, ConfigTpl: mysql-consensusset-config, info: updated: map[my.cnf:{"mysqld":{"innodb_buffer_pool_size":"512M","max_connections":"600"}}], added: map[], deleted:map[]
    Mar 13,2023 02:55 UTC+0800 ReconfigureSucceed ReconfigureSucceed True Reconfiguring in Cluster: mysql-cluster, Component: mysql, ConfigTpl: mysql-consensusset-config, info: updated policy: <autoReload>, updated: map[my.cnf:{"mysqld":{"innodb_buffer_pool_size":"512M","max_connections":"600"}}], added: map[], deleted:map[]
    Mar 13,2023 02:55 UTC+0800 Succeed OpsRequestProcessedSuccessfully True Successfully processed the OpsRequest: mysql-cluster-reconfiguring-z2wvn in Cluster: mysql-cluster
  4. Connect to the database to verify whether the parameters are configured as expected.

    The whole searching process has a 30-second delay since it takes some time for kubelet to synchronize modifications to the volume of the pod.

    kbcli cluster connect mysql-cluster
    mysql> show variables like '%max_connections%';
    >
    +-----------------+-------+
    | Variable_name | Value |
    +-----------------+-------+
    | max_connections | 600 |
    +-----------------+-------+
    1 row in set (0.04 sec)
    mysql> show variables like '%innodb_buffer_pool_size%';
    >
    +-------------------------+-----------+
    | Variable_name | Value |
    +-------------------------+-----------+
    | innodb_buffer_pool_size | 536870912 |
    +-------------------------+-----------+
    1 row in set (0.00 sec)

Configure parameters with edit-config command

For your convenience, KubeBlocks offers a tool edit-config to help you configure parameters in a visualized way.

For Linux and macOS, you can edit configuration files by vi. For Windows, you can edit files on the notepad.

The following steps take configuring MySQL Standalone as an example.

  1. Edit the configuration file.

    kbcli cluster edit-config mysql-cluster --config-spec=mysql-consensusset-config
    note
    • Since ApeCloud MySQL currently supports multiple templates, it is required to use --config-spec to specify a configuration template. You can run kbcli cluster describe-config mysql-cluster to view all template names.
    • If there are multiple components in a cluster, use --component to specify a component.
  2. View the status of the parameter configuration.

    kbcli cluster describe-ops xxx -n default
  3. Connect to the database to verify whether the parameters are configured as expected.

    kbcli cluster connect mysql-cluster
    note
    1. For the edit-config function, static parameters and dynamic parameters cannot be edited at the same time.
    2. Deleting a parameter will be supported later.

View history and compare differences

After the configuration is completed, you can search the configuration history and compare the parameter differences.

View the parameter configuration history.

kbcli cluster describe-config mysql-cluster
>
ConfigSpecs Meta:
CONFIG-SPEC-NAME FILE ENABLED TEMPLATE CONSTRAINT RENDERED COMPONENT CLUSTER
mysql-consensusset-config my.cnf true mysql8.0-config-template mysql8.0-config-constraints mysql-cluster-mysql-mysql-config mysql mysql-cluster

History modifications:
OPS-NAME CLUSTER COMPONENT CONFIG-SPEC-NAME FILE STATUS POLICY PROGRESS CREATED-TIME VALID-UPDATED
mysql-cluster-reconfiguring-4q5kv mysql-cluster mysql mysql-consensusset-config my.cnf Succeed reload -/- Mar 16,2023 15:44 UTC+0800 {"my.cnf":"{\"mysqld\":{\"max_connections\":\"3000\",\"read_buffer_size\":\"24288\"}}"}
mysql-cluster-reconfiguring-cclvm mysql-cluster mysql mysql-consensusset-config my.cnf Succeed reload -/- Mar 16,2023 17:28 UTC+0800 {"my.cnf":"{\"mysqld\":{\"innodb_buffer_pool_size\":\"1G\",\"max_connections\":\"600\"}}"}
mysql-cluster-reconfiguring-gx58r mysql-cluster mysql mysql-consensusset-config my.cnf Succeed -/- Mar 16,2023 17:28 UTC+0800

From the above results, there are three parameter modifications.

Compare these modifications to view the configured parameters and their different values for different versions.

kbcli cluster diff-config mysql-cluster-reconfiguring-4q5kv mysql-cluster-reconfiguring-gx58r
>
DIFF-CONFIGURE RESULT:
ConfigFile: my.cnf TemplateName: mysql-consensusset-config ComponentName: mysql ClusterName: mysql-cluster UpdateType: update

PARAMETERNAME MYSQL-CLUSTER-RECONFIGURING-4Q5KV MYSQL-CLUSTER-RECONFIGURING-GX58R
max_connections 3000 600
innodb_buffer_pool_size 128M 1G