topic vgimport with different vgname in Operating System - HP-UX

vgimport with different vgname

akarayil — Wed, 04 Nov 2009 11:44:41 GMT

Hi

I'm little bit confused over one of our current settings. We have two EVA storages and data replication (CA)is enabled between them.There are two hpux servers (2 node cluster) on PRIMARY site and a single server on DR site. There is one shared VG between cluster nodes. For this LUN, a DataReplication group is created in storage and the LUN in DR storage is presented to the hpux server in DR site.

I'm confused about the vgname used in PRI and DR site. In cluster nodes,same vgname is used, but in DR server the VG name is different (with different minor no.).

Suppose I create a vg and export it with a name vg01. On the other system I create a dir with a name /dev/vg02, then create the dev file with different minor no. I import map file using the command.
vgimport -s -v -m /etc/lvmconf/map.vg01 /dev/vg02
Is this work?
Here I would like to make this vg as cluster aware and add to the package control script.

Re: vgimport with different vgname

melvyn burnard — Wed, 04 Nov 2009 13:03:20 GMT

so you have a 2 node cluster at the Primary site, and a single node (not part of the cluster ) ayt the DR site?
Then it doesn't matter if it has a different VG name.
Your vgexport/import example would work, UNLESS the 3rd server IS a part of the cluster

Re: vgimport with different vgname

Kapil Jha — Wed, 04 Nov 2009 13:09:59 GMT

it would work without any issue and it should work on cluster node as well if thats not part of cluster config (which would never happen)

It would work if vg01 belong to a package and on other node you are importing it as vg02, the only thing to keep in mind is you would be having different scripts on 2 boxes to handle package as your vg name is different.

BR,
Kapil+

Re: vgimport with different vgname

Suraj K Sankari — Wed, 04 Nov 2009 13:24:09 GMT

Hi,
Yes it will work. if it is a 2 node cluster..

Suraj

Re: vgimport with different vgname

Bill Costigan — Wed, 04 Nov 2009 13:55:58 GMT

VG names and minor numbers are local to the server. They are not written to the disks. It is the VGID that ties stuff together on the disks.

While it is nice to use the same name for the same volume group on all servers, it's more to keep the admin person sane. HPUX doesn't care.

Re: vgimport with different vgname

Vishu — Wed, 04 Nov 2009 17:58:30 GMT

Hi,

It will work for sure. /etc/lvmtab maintains the VG database and it is local to the server. It has nothing to do with the cluster. But having same VG names in cluster makes Sys_Admin job easier to troubleshoot.

A exported VG can be imported with a new name on the server.

Re: vgimport with different vgname

akarayil — Thu, 05 Nov 2009 06:12:59 GMT

Thanks for the support.
So I can go ahead with adding this vg to the package.Correct me if any mistake in the following steps.
-Add vgname to cluster configuration file(optional) and vg and lv info to pkg control script.
-Copy pkg cntl script to the other node.
#vgchange -c y vgxx
#vgchange -a n vgxx
#cmhaltpkg -v PKG
#cmrunpkg -v PKG
#cmmodpkg -e PKG
I think as I'm not making any changes in package conf file, I dont need to run cmcheckconf and amapplyconf cmds.

Re: vgimport with different vgname

akarayil — Fri, 06 Nov 2009 11:01:17 GMT

Any Suggestion would be appreciated

Re: vgimport with different vgname

Bill Costigan — Fri, 06 Nov 2009 14:04:28 GMT

The steps look fine. The only change I might make is to add the VG and LV changes to the script file after the package is halted.

If you make the changes before the package is halted, the control script will try to unmount the file systems and deactivate the VG even though this is not necessary.

I doubt it would cause any problems even if it tried except maybe logging a few warnings in the control script log file.

Re: vgimport with different vgname

akarayil — Mon, 09 Nov 2009 11:38:49 GMT

Thank you