For a real Oracle Grid environment with 7 Oracle Virtual Servers, today I had to configure a shared "/OVS" directory on OCFS2.
Oracle VM Server provides a great option to share the Oracle VM guest images on a shared location with a shared filesystem.
With that, you can do live migrations and/or make the guests available on other machines.
Also with a shared filesystem an Oracle VM can be made high available.
All went well, but after four nodes I received a message about the maximum number of slots being used.
Because of that I was not able to mount the filesystem on nodes 5,6 and 7.
In order to mount the shared filesystems, I had to:
- unmount the filesystem on all nodes
- execute tunefs.ocfs2 -N [number of nodes] /dev/my-block
- and mount the flesystem
Below you can see the number of slots is changed from 4 to 7.
[root@nlblade07 ~]# tunefs.ocfs2 -q -Q "%N" /dev/sda
4[root@nlblade07 ~]# tunefs.ocfs2 -N 7 /dev/sda
tunefs.ocfs2 1.2.7
Changing number of node slots from 4 to 7
Proceed (y/N): y
Changed node slots
Resized journals
Wrote Superblock
[root@nlblade07 ~]# tunefs.ocfs2 -q -Q "%N" /dev/sda
7
Rene Kundersma
Oracle Expert Services, The Netherlands
