Inventory pointer file in RAC DBs

Question

Grid version:11.2.0.3
DB versions: 11.2.0.3, 10.2.0.5
Platform : Solaris / AIX
In our RAC servers, I have noticed that the inventory pointer file (oraInst.loc) of RDBMS HOMEs point to the Grid inventory
--- inventory pointer file of 11.2.0.3 GRID HOME
$ cat /u01/grid/11.2/oraInst.loc
inventory_loc=/u01/grid/11.2/oraInventory
inst_group=dba-- inventory pointer file of a 10.2.0.5 RDBMS HOME running in this cluster
$ cat /u01/oracle/10.2/db/oraInst.loc
inventory_loc=/u01/grid/11.2/oraInventory
inst_group=dba-- inventory pointer file of a 11.2.0.3 RDBMS HOME running in this cluster
$ cat /u01/oracle/11.2/db/oraInst.loc
inventory_loc=/u01/grid/11.2/oraInventory
inst_group=dbaIs this a pre-requisite or a standard practice ?

Answer 1

In Solaris, the default location for the inventory location file is /var/opt/oracle/oraInst.loc. Make sure they all point to the same inventory and make sure they are all up-to-date. You also want to make sure that this "global/central" inventory has READ/WRITE for grid and oracle users. You can take an existing inventory (or delete all of them) and use the runInstaller to create and/or add a new home;
Start here:
http://docs.oracle.com/cd/E11882_01/em.112/e12255/oui2_manage_oracle_homes.htm
look for
./runInstaller -silent -attachHome ORACLE_HOME="<Oracle_Home_Location>"
"CLUSTER_NODES={<node1,node2>}" LOCAL_NODE="<node_name>" <<--note for clusters, the "local_node" - so do this on all nodes
There is also a "detachHome"