topic Service Guard & EMC BCV's in Operating System - HP-UX

Service Guard & EMC BCV's

Glen Hyatt — Wed, 12 Dec 2001 03:28:45 GMT

I am using EMC's Timefinder software to do backups of an oracle database on a SG cluster. Once the BCV volumes are synchronised with the originals, they are then re-imported onto the cluster by running a vgchange -c n, a vgchgid and then vgimport with a new vg name. My problem is this: If I wish to restore from this copy, what steps do I need to do on the cluster. Once the restore is complete, the volume group ID will be different to the originals (& what's in lvmtab)as we have run a vgchgid.

My thoughts were...
1. run vgcfgrestore onto the disks once the restore was complete.
OR
2. vgexport the original volumes, vgimport using the same names, then vgchange -c y the originals & then vgchgid the BCV's again so the VGID's aren't duplicated once more.

If anyone has experience with this or has any ideas it would be greatly appreciated.

Thanks, Glen.

Re: Service Guard & EMC BCV's

Ian Dennison_1 — Wed, 12 Dec 2001 09:29:33 GMT

How quick is a 'symmir -restore' command? If you unmount both file systems and perform the restore this way, you can continue to use the Standard Volumes and their BCV in the normal way. EMC have a new set of microcode for the Array that provides mega-quick splits and synchs, and possibly restores.

Are you planning to disassociate the BCVs with the Standard Devices before remounting them?

Personally, the shortest route is to unmount the Standard Volumes and remount the BCV Volumes on the regular mount points (ie leave the Volume Groups as they are). This involves the least number of OS changes, and will make the data on the BCV available to the Application. You may incur some procedural overhead in this (remember to update the /etc/fstab, and to prevent resynchs while running on the BCV Disks), but this can be scripted fairly easily.

Share and Enjoy! Ian

Re: Service Guard & EMC BCV's

Pashupati Kumar — Fri, 28 Jun 2002 01:46:31 GMT

hi,
Once you are done restoring from the BCVs, you unmount all the fs and deactivate the volume groups existing on BCVs. Re-establish the BCVs with Standard. As part of re-establishing, the changed blocks on BCVs ( due to vgchgid and vgimport with different name)are dumped with the content from standard device. BCV device are also written back all the blocks which changed on the std since the BCV was split.

thanks
pash