vgchange commands in serviceguard

[P Arumugavel]

Hi Experts,

In hp-ux serviceguard cluster, where do we use commands like vgchange -a y/n/e/r, vgchange -c y/n and vgchange -S y/n.

In which situations we will use these commands. Please give me clearly for which makes me bit of confuse.

Thanks in advance.

[melvyn burnard]

man vgchange

Also, read the Managing Serviceguard manual from the document library
http://h20000.www2.hp.com/bizsupport/TechSupport/DocumentIndex.jsp?lang=en&cc=us&taskId=101&prodClassId=10008&contentType=SupportManual&docIndexId=64255&prodTypeId=18964&prodSeriesId=4162060

[Steven E. Protter]

Shalom,

http://docs.hp.com/en/B2355-90681/vgchange.1M.html

Activate volume group

/usr/sbin/vgchange -a availability [-l] [-p] [-q quorum] [-s] [-P resync_daemon_count] [vg_name...]
Assign to high availability cluster and mark volume group sharable

/usr/sbin/vgchange -c cluster -S sharable vg_name

SEP

[Ismail Azad · Accepted solution]

Hi P,

vgchange -c y makes the volume group "cluster aware" and once this is done when you are using the "failover type" package and the disk partitioning approach as LVM, writing onto the same space of a shared disk can cause corruption to the V.G if you are not using higher volume managers that are aware of such reads/writes and do_not cause corruption. This post is based on classical_LVM and not_SLVM.

Using LVM, in order to avoid corruption, you can "exclusively activate" the volume group so that the confusion of a node having different views of the filesystem is nullified. Once you have executed...

vgchange -c y vg01, now you can execute
vgchange -a e vg01 on node1 as long as V.G is not activated on node2.

On node 2 of the cluster now if you execute..
vgchange -a e vg01... you get an error... However, you can still execute...
vgchange -a r vg01 in read only mode on node2

To activate exclusively on node2. On node1 execute...
vgchange -a n vg01.
On node2 now...
vgchange -a e vg01 should work!.

Hope you got the term "exclusive activation".

Regards
Ismail Azad

[P Arumugavel]

Thanks a lot Ismail.

You gave me what I expected...

[P Arumugavel]

Thanks a lot Ismail.

You gave me what I wanted.