Just a quick blog entry. I have installed 11g RAC quite a few times already and just wanted to share with you folks an observation.
Those of you who have installed 10gR2 Clusterware (CRS) know that towards the end of the CRS installation you have to go from node to node and execute $ORA_CRS_HOME/root.sh. When you run it on the last node the script will try to set up VIPs (this is why you have to run the CRS root.sh as root in an xterm because it is a window-less JAVA app). Oracle1gR2 has had an annoying bug in it that failed the VIP setup because it was very picky about the IP addresses you assigned to VIPs. The workaround for that was to ignore the problem and then invoke $ORA_CRS_HOME/bin/vipca and walk through the setup of VIPs (including GSD and so on). It was a minor problem that was easy to work around.
10g and 11g Clusterware Co-Existence
I have not seen that problem with 11g. In fact, the reason I’m blogging this is because I just walked through an install of 10gR2 Clusterware on my cluster running x86 RHEL4 attached to NAS (NFS). I need a setup where I have both 10g and 11g clusterware installed and I need to be able to “hide” and “expose” either with a few simple commands to test one or the other. After the successful install of 10gR2 CRS, I “hid it” (to include all the residue in /etc) and proceeded to install 11g CRS. Since I just did both 10gR2 CRS and 11g CRS installs back to back I was reminded that 10gR2 CRS has that pesky problem and I did have to hand-invoke vipca to get through it. I was pleasantly reminded, however, that 11g does not have that problem.
For those of you who are used to seeing the complaint about VIPs at the conclusion of the last root.sh execution, see the following screen shot from 11g and breathe a sigh of relief.
And a picture speaks a thousand words so here is a shot of my little 11g NAS RAC clusterware setup:
Note to self: Investigate whether 11g CRS works with 10gR2 RAC instances and make a blog entry. It should, so I will.