Oracle RAC 11.2 Server Pools

Server Pools

There is nothing unusual with 11.2 server pools, but when it comes to nested pools there are some unexpected glitches. First, it looks like the standard "srvctl" command doesn't support nested server pools at all (as of version 11.2) - if you want a nested pool, you have to modify its attribute with crsctl. After you change a pool with crsctl you won't be even able to read its configuration using srvctl anymore.

Lets create a nested server pool:

$ srvctl add srvpool -g avif -l 1 -u 3 -n "lab241"

$ srvctl status srvpool -g avif -a

$ crsctl status serverpool -f

$ srvctl add srvpool -g avifapp -l 1 -u 2
$ srvctl add srvpool -g avifbat -l 1 -u 1 -i 100

$ crsctl modify srvpool ora.avifapp -attr "PARENT_POOLS=ora.avif"
$ crsctl modify srvpool ora.avifapp -attr "IMPORTANCE=200"

$ crsctl modify srvpool ora.avifbat -attr "PARENT_POOLS=ora.avif"

$ crsctl status serverpool ora.avifapp -f

$ crsctl modify srvpool ora.avifbat -attr "PARENT_POOLS="
$ crsctl modify srvpool ora.avifapp -attr "PARENT_POOLS="
 

Srvctl seems to be completely confused when you alter the configuration of pools with crsctl. Adding a nested pool to a pool makes it invisible to srvctl, you cannnot even start up an instance using srvctl. When you query the database's config, it shows the database is admin managed - despite the fact previously it was policy managed. So it is all messed up.

Bugs

$ crsctl modify srvpool ora.avifapp -attr "EXCLUSIVE_POOLS=AVIF"
CRS-2596: Modifications to the 'EXCLUSIVE_POOLS' attribute of
          server pools are not supported
CRS-4000: Command Modify failed, or completed with errors.

$ srvctl modify srvpool -g avifapp -i 200
PRKO-3130 : Server pool avifapp is internally managed as part of
            administrator-managed database configuration and
            therefore cannot be modified directly via srvpool object. 

Today's comment of MOS (26 March 2014): It is not supported to modify the value of EXCLUSIVE_POOLS to some string.

Resources

1. Server Pools Attributes (11.2)
2. A blog article about Server Pools (11.2) with some interesting bug catches.