Table of Contents
What is a Server Pool?
- Server pools enable the cluster administrator to create a policy which defines how Oracle Clusterware allocates resources.
- An Oracle RAC policy-managed database runs in a server pool.
- Oracle Clusterware attempts to keep the required number of servers in the server pool and, therefore, the required number of instances of the Oracle RAC database.
- A server can be in only one server pool at any time. However, a database can run in multiple server pools.
- Cluster-managed services run in a server pool where they are defined as either UNIFORM (active on all instances in the server pool) or SINGLETON (active on only one instance in the server pool).
Display and manage serverpools
Check the current servers and there status: $ crsctl get cluster mode status Cluster is running in "flex" mode $ crsctl get node role status -all Node 'gract1' active role is 'hub' Node 'gract2' active role is 'hub' Node 'gract3' active role is 'leaf' $ srvctl status srvpool -detail Server pool name: Free Active servers count: 0 Active server names: Server pool name: Generic Active servers count: 0 Active server names: Server pool name: 12c_pool Active servers count: 3 Active server names: gract1,gract2,gract3 NAME=gract1 STATE=ONLINE NAME=gract2 STATE=ONLINE NAME=gract3 STATE=ONLINE $ crsctl status serverpool -p NAME=Free IMPORTANCE=0 MIN_SIZE=0 MAX_SIZE=-1 SERVER_NAMES= PARENT_POOLS= EXCLUSIVE_POOLS= ACL=owner:grid:rwx,pgrp:oinstall:rwx,other::r-x SERVER_CATEGORY= NAME=Generic IMPORTANCE=0 MIN_SIZE=0 MAX_SIZE=-1 SERVER_NAMES= PARENT_POOLS= EXCLUSIVE_POOLS= ACL=owner:grid:r-x,pgrp:oinstall:r-x,other::r-x SERVER_CATEGORY= NAME=ora.12c_pool IMPORTANCE=0 MIN_SIZE=3 MAX_SIZE=3 SERVER_NAMES= PARENT_POOLS= EXCLUSIVE_POOLS= ACL=owner:oracle:rwx,pgrp:oinstall:rwx,other::r-- SERVER_CATEGORY=ora.hub.category Create a new serverpool with a higher priority $ srvctl add serverpool -serverpool NEW_12c_pool -min 1 -max 2 -i 5 PRCS-1009 : Failed to create server pool NEW_12c_pool PRCR-1071 : Failed to register or update server pool ora.NEW_12c_pool CRS-2736: The operation requires stopping resource 'ora.gract1.db' on server 'gract1' CRS-2737: Unable to register server pool 'ora.NEW_12c_pool' as this will affect running resources, but the force option was not specified --> Use force option to create the new serverpool and check the status $ srvctl add serverpool -serverpool NEW_12c_pool -min 1 -max 2 -i 5 -f $ srvctl status serverpool -detail Server pool name: Free Active servers count: 0 Active server names: Server pool name: Generic Active servers count: 0 Active server names: Server pool name: 12c_pool Active servers count: 2 Active server names: gract2,gract3 NAME=gract2 STATE=ONLINE NAME=gract3 STATE=ONLINE Server pool name: NEW_12c_pool Active servers count: 1 Active server names: gract1 NAME=gract1 STATE=ONLINE --> gract1 is moved from 12c_pool to NEW_12c_pool