I would be very interested to hear from Netapp contributors if NDMP backups of volume snapmirror’s has changed. My education at the time was that volume level snapmirror’s are RO for all blocks, which means inode pointers could not change since that meant a change to blocks *in* the volume.
QSM/Snapvault has never suffered from this issue.
Jeff Kennedy
Qualcomm, Incorporated
QCT Engineering Compute
858-651-6592
From: Jeremy Webber
[mailto:Jeremy.Webber@al.com.au]
Sent: Sunday, November 21, 2010 6:22 PM
To: Kennedy, Jeffrey
Cc: Jeremy Webber; Fred Grieco; toasters@mathworks.com
Subject: Re: NDMP backup of snapmirror target
Maybe there were limitations in earlier versions of OnTAP but I can confirm that we do tape backups, via tape, from a snapmirror destination without having to break the snapmirror relationship.
A snapshot is automatically created in the snapmirror destination for the duration of the NDMP job.
I can't recall if subsequent snapmirror updates fail during the backup and am not able to test this right now.
OnTAP 7.3.2.
-jeremy
On 17/11/2010, at 6:11 AM, Kennedy, Jeffrey wrote:
Things may have changed in OT since I last was concerned with tape backups but as I recall a snapmirrored *volume* can’t take the backup snapshot because it’s RO. So you point the backup software at the newest snapshot in the RO volume and back up that view.
The only reason the NDMP backup makes a snapshot is to guarantee consistency. An existing snapshot already has that.
Jeff Kennedy
Qualcomm, Incorporated
QCT Engineering Compute
858-651-6592
From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Fred Grieco
Sent: Tuesday, November
16, 2010 6:26 AM
To: toasters@mathworks.com
Subject: NDMP backup of
snapmirror target
I am
snapmirroring several volumes to a DR site, and I would like to do tape backups
at that site. How should I do them? Can I use NDMP?
It seems like I can't do straight NDMP because the replicated target is
read-only. I am currently creating flexclones from snapshots existing in
the volume (nightly.0...) but flexclone then locks this snapshot and snapmirror
will fail to update ( I'm not sure if this happens at the next update or
when the source system attempts to remove that snapshot and copy it over... I
wasn't watching).
What do you generally do to get snapmirrored volume data to tape?
TIA,
Fred
--
Jeremy Webber
Senior Systems Engineer
Animal Logic Pty Ltd
T: +61 2 9383 4837
F: +61 2 9383 4801