8.5.1 Setting Options for InnoDB Cluster

You can check and modify the settings in place for an InnoDB Cluster while the instances are online. To check the current settings of a cluster, use the following operation:

Cluster.options(), which lists the configuration options for the cluster and its instances. A Boolean option all can also be specified to include information about all Group Replication system variables in the output.

You can configure the options of an InnoDB Cluster at a cluster level or instance level, while instances remain online. This avoids the need to remove, reconfigure and then again add the instance to change InnoDB Cluster options. Use the following operations:

Cluster.setOption(option, value) to change the settings of all cluster instances globally or cluster global settings such as clusterName.
Cluster.setInstanceOption(instance, option, value) to change the settings of individual cluster instances

The way which you use InnoDB Cluster options with the operations listed depends on whether the option can be changed to be the same on all instances or not. These options are changeable at both the cluster (all instances) and per instance level:

autoRejoinTries: integer value to define the number of times an instance attempts to rejoin the cluster after being expelled. See Section 8.5.5, “Configuring Automatic Rejoin of Instances”.
exitStateAction: string value indicating the Group Replication exit state action. See Section 8.5.5, “Configuring Automatic Rejoin of Instances”.
memberWeight: integer value with a percentage weight for automatic primary election on failover. See Section 8.5.3, “Configuring the Election Process”.
ipAllowList: comma-separated list of IP addresses or subnet CIDR notation. For example: 192.168.1.0/24,10.0.0.1. By default the value is set to AUTOMATIC, allowing addresses from the instance private network to be automatically set for the allowlist.
Note
This option can only be set if the communicationStack is set to XCOM.
tag:option: built-in and user-defined tags to be associated to the cluster. See Section 6.9, “Tagging Metadata”.

The following options are changeable at the cluster level only:

clusterName: string value to define the cluster name
disableClone: Boolean value used to disable the clone usage on the cluster. See dba.createCluster() and MySQL Clone.
replicationAllowedHost: string value to define strict subnet based filtering, so that internally managed replication accounts can only connect from allowed hosts. See InnoDB Cluster replicationAllowedHost.
expelTimeout: integer value to define the time period in seconds that cluster members should wait for a non-responding member before evicting it from the cluster. See Section 8.4.3, “Creating an InnoDB Cluster”.
transactionSizeLimit: positive integer value which sets the Group Replication system variable group_replication_transaction_size_limit. This sets the maximum transaction size in bytes which the cluster accepts. Larger transactions are rolled back and not broadcast to the cluster. All members added to the cluster use the same value.

The following option is changeable at the per instance level only:

label: a string identifier of the instance