Remove a resource pool from a tenant

You can execute the ALTER TENANT statement to remove a resource pool from a tenant.

Syntax

The syntax for removing a resource pool from a tenant is as follows:

ALTER TENANT tenant_name RESOURCE_POOL_LIST [=](pool_name [, pool_name...]) ;

Some notes about this:

• This statement can be executed only by the administrator of the sys tenant.

• This statement can delete only one resource pool specified by RESOURCE_POOL_LIST at a time.

Usually, you can remove a resource pool from a tenant to decrease the number of replicas of the tenant.

Sample scenario

A cluster spans zones z1, z2, z3, z4, and z5 that belong to the same region, and one OBServer node is deployed in each zone. The cluster has a normal tenant named tenant1. The locality information is locality='F@z1,F@z2,F@z3,F@z4,F@z5', resource_pool_list=('pool1','pool2'), and the resource distribution in the resource pools is defined by CREATE RESOURCE POOL pool1 UNIT 'uc1', UNIT_NUM 1, ZONE_LIST ('z1', 'z2', 'z3') and CREATE RESOURCE POOL pool2 UNIT 'uc2', UNIT_NUM 1, ZONE_LIST ('z4', 'z5').

Based on business needs, the number of replicas of tenant1 needs to be decreased from 5 to 3, and the number of resource pools needs to be decreased to 1. That is, the locality of the tenant needs to be changed to locality='F@z1,F@z2,F@z3,', resource_pool_list=('pool1').

Sample procedure

1. Log on to the sys tenant of the cluster as the root user.

2. Modify the locality of tenant1 to delete replicas in z4:

   Based on the locality modification rule, you can delete only one zone at a time. For more information about the locality modification rule, see Overview of localities.

   obclient>ALTER TENANT tenant1 LOCALITY='F@z1,F@z2,F@z3,F@z4';
   
   obclient>ALTER TENANT tenant1 LOCALITY='F@z1,F@z2,F@z3';
   

3. Delete the pool2 resource pool from z4 and z5.

   obclient>ALTER TENANT tenant1 RESOURCE_POOL_LIST =('pool1') ;
   

More information

In other scenarios, you can modify the configurations and number of resource units in a resource pool to adjust the resources available for a tenant. For information about how to modify the configurations of a resource unit, see Modify configurations of a resource unit. For information about how to modify the number of resource units in a resource pool, see Modify a resource pool.