This topic describes how to modify the replica type and unit specification of tenant replicas in a single zone.
Note
Modifying the unit specification will trigger a partition replica migration operation, increasing the storage I/O on OBServer nodes and the network traffic between OBServer nodes. To manage sudden traffic, we recommend that you adjust the parameter values of ha_high_thread_score and ha_mid_thread_score, or implement resource isolation for the background tasks HA_HIGH and HA_MID.
Prerequisites
The login user has the following permissions:
- Cluster Maintenance or Tenant Maintenance permissions.
- The Overview menu permission of the tenant.
Starting from V4.0.0, clusters will default to limiting the unit specifications. If you need to select a unit specification smaller than the cluster's default, you can adjust the minimum value limit using the
__min_full_resource_pool_memoryparameter. For example, in a V4.1.0 cluster, you can refer to the steps provided in Modify cluster item configurations.If the tenant belongs to a cluster V4.2.0 or later, and the tenant parameter
enable_rebalanceis set tofalse, you cannot modify the number of units in the zone.If the replica type is Read-Only Columnar Replica, you cannot change it to another type. If the replica type is Universal Replica or Read-Only Replica, you cannot change it to a Read-Only Columnar Replica.
If the tenant is a standalone database, you cannot modify the replica type.
Procedure
Log in to the OCP console.
In the left-side navigation pane, select Tenant. The Tenants page automatically appears.
In the Tenants list on the Overview page of the tenant, find the target tenant and click its name.
In the Replica Details section, select the zone whose replica type and unit specification you want to modify and click Edit.
Note
- We recommend that the resources of the units remain consistent within the tenant.
- For more information, see the descriptions of replica type, unit specification, and unit count in Create a tenant.
Click OK.