topic Re: MSA2000: Multiple Snapshots, data consistency in HPE EVA Storage

MSA2000: Multiple Snapshots, data consistency

Rob_69_1 — Thu, 21 Jan 2010 17:01:36 GMT

Hi all, I'd like to know if, taking snapshots of more than one Volume at the same time, using a single command, e.g.:

create snapshots master-volumes DATA_01,DATA_02 SNAP_01,SNAP_02

would result in a consistent "situation", should a rollback of ALL the volumes be necessary for any reasons.

For instance: a Database with data files spreaded on different Volumes. In case of rollback, would data be consistent?

I think the mechanism should be meant to provide consistency, otherwise it wouldn't be possible to specify more than one snapshot creation at a time, within a single statement. But I'd like to be sure.

Thank you for any insights...

PS as stated in the subject, the SAN storage is an MSA2000 (2012FC)

Re: MSA2000: Multiple Snapshots, data consistency

Rob_69_1 — Tue, 26 Jan 2010 10:43:00 GMT

...Anyone? Please?

Re: MSA2000: Multiple Snapshots, data consistency

Dan Pyper — Sat, 30 Jan 2010 07:08:01 GMT

Yes, the MSA2000 products will perform a time consistent snap of ALL volumes specified on the CLI command line.

Your desire to create a data consistent snapshot of multiple volumes is possible as long as your ensure each OS logical drive using such MSA2000 volumes are quiesced so the I/O is flushed prior to your snap shot time.

Re: MSA2000: Multiple Snapshots, data consistency

Rob_69_1 — Sat, 30 Jan 2010 10:40:25 GMT

Hi Dan, thanks for your feedback.

Can you please be a bit more specific and bring a practical example of "logical drives" needing to be quiesced at OS level, prior taking the snapshot(s)?

In my understanding, a snapshot can be taken without stopping I/O to the disks... But maybe you were referring to things like "LVOL" or other software tools to sub-partition "hardware defined" Logical Volumes / LUNs ?

Thanks again.