We are planning for a new OEM 12C fresh installation implementation. I was reading a white paper and had a few questions.
As per the white paper the implementation they had done was divided into OMS tier where they had 2 OMS servers which were load balanced and repository tier for the cloud control repository database for which they had used a 2 node RAC database with 11gR2 installed and also had a 2 node RAC physical standby database with active dataguard. The 2 node rac standby database was also for the database repository for cloud control. SO here we have 6 boxes. 2 for the OMS servers, 2 for the primary 2node RAC db and 2 for the standby.
Below are my questions
1) Can we have a 2 node RAC database with 11gR2 and install OEM 12C on the same RAC database? This way can we eliminate the need for the separate OMS servers.
If yes is this recommended by Oracle? My guess is since OEM is part of middleware and RAC is a database tier both of these have to be seperated in a real time env.
Pls note that we are planning to implement 12c OEM to manager over 5000 targets so this is a big implementation.
2) As part of the advance installation guide i see that 3 tablespaces are created when installing OEM for which we assign 2 datafiles. Is there a recommendation by oracle on how much minimum size should be each of this datafile if we are planning to manage about 5000 targets?
1) It is not a requirement to host the database and OMS on dedicated servers, but it is desirable.
- reduces resource contention
- can simplify maintenance
2) 500 targets is not a stretch for 12c -- this would be a medium-sized site.
See Enterprise Manager Cloud Control Advanced Installation and Configuration Guide 12c Release 2 (188.8.131.52):
+11: Sizing Your Enterprise Manager Deployment+ especially +184.108.40.206 Repository Tablespace Sizing+