Friday, April 23, 2010

11gR2: adding a mirrored voting disk on OCFS2 file system

I want to add a mirrored voting disk after migration from ASM to OCFS2.
The following is my current configuration:
/u01/app/11.2.0/grid/bin/crsctl query css votedisk
## STATE File Universal Id File Name Disk group
-- ----- ----------------- --------- ---------
1. ONLINE 353efdf9e50d4f93bf71c6aa84b9e19b (/u02/ocfs2/css/vdisk) []
Located 1 voting disk(s).


Create a new directory on mirrored location


Set the right permissions, as I did:
touch css/vdisk
chown -R oracle.oinstall css/

and check if all is right

Now execute the command to add another voting disk:
/u01/app/11.2.0/grid/bin/crsctl add css votedisk /u02/ocfs2_mirror/css/vdisk
Now formatting voting disk: /u02/ocfs2_mirror/css/vdisk.
CRS-4603: Successful addition of voting disk /u02/ocfs2_mirror/css/vdisk.

As you can see, I have now two voting disk files.
/u01/app/11.2.0/grid/bin/crsctl query css votedisk
## STATE File Universal Id File Name Disk group
-- ----- ----------------- --------- ---------
1. ONLINE 353efdf9e50d4f93bf71c6aa84b9e19b (/u02/ocfs2/css/vdisk) []
2. ONLINE 0c254a5cdcd14f9bbfef2866447e908c (/u02/ocfs2_mirror/css/vdisk) []
Located 2 voting disk(s).


But what about if I want to have a mirrored copy also on Oracle ASM ?
It's simply not possible even if from the documentation I didn't find about it.
/u01/app/11.2.0/grid/bin/crsctl add css votedisk +DATA_RAC3
CRS-4671: This command is not supported for ASM diskgroups.
CRS-4000: Command Add failed, or completed with errors.

The command is not supported. I can mention this documentation note from "Clusterware Administration and Deployment Guide" (e10717.pdf):
Oracle does not support storing the OCR on different storage types simultaneously, such as storing OCR on both Oracle ASM and a shared file system, except during a migration.


That's all.