It looks like Matt has a solution that should work.  Additionally, if this is a unix system, on a high level, you can parse the output and use 'tail' to establish the eligible snapshot for deletion.
 
On another note, make sure that you are 100% sure that the switch to 'hot-backup' mode was successful and completed before starting the snapshot process.  Also be 100% sure that the snapshot has completed before coming out of 'hot-backup' mode.  Yes, I've seen situations before where these checks and balances would have been helpful.  Also make sure that these checks are written out to a log file in case you ever need to go back to troubleshoot.
 
Good luck
 

Stetson M. Webster
Managed Services Engineering
NetApp Global Services - Southeast District

919.250.0052 Mobile
Stetson.Webster@netapp.com
www.netapp.com
 

From: Leeds, Daniel [mailto:dleeds@edmunds.com]
Sent: Tuesday, August 05, 2008 12:51 PM
To: Daniel Keisling; Stephen C. Losen
Cc: toasters@mathworks.com
Subject: RE: Automatically delete snapshots based on number and not space availability

snapvault.


snapvault snap sched  myvol sv_daily 5@-


say its oracle on the host:

backup script puts instance in hotbackup mode
snapvault snap create myvol sv_daily
backup script takes instance out of hotbackup mode


(cold backup shutdown/startup same way)

it will automatically keep 5 snapshots rotate the oldest and the - allows you to take the snap anytime via the script


--
Daniel Leeds
Manager, Storage Operations
Edmunds, Inc.
1620 26th Street, Suite 400 South
Santa Monica, CA 90404

310-309-4999 desk
310-430-0536 cell



-----Original Message-----
From: owner-toasters@mathworks.com on behalf of Daniel Keisling
Sent: Tue 8/5/2008 9:38 AM
To: Stephen C. Losen
Cc: toasters@mathworks.com
Subject: RE: Automatically delete snapshots based on number and not space availability

Everyone is assuming that the NetApp will be taking the snapshots, which
is incorrect.  I must do the snapshots from the host side in order to
quiesce the filesystem (actually, the database).  My databases run on
LUNs over FCP.  I do not want to try and coordinate the databases on the
host being quiesced at the same time the filer will automatically take
the snapshot.

Daniel

-----Original Message-----
From: Stephen C. Losen [mailto:scl@sasha.acc.Virginia.EDU]
Sent: Tuesday, August 05, 2008 11:01 AM
To: Daniel Keisling
Cc: toasters@mathworks.com
Subject: Re: Automatically delete snapshots based on number and not
space availability

> Greetings,
> 
> I take a daily snapshots (named ss-YYYYMMDDHHmm) of several volumes on
> my filers.  I would like to automatically delete the oldest snapshot
> (assuming it's not busy) when a certain number of snapshots are
present
> in the volume (ie, only keep the latest 3 snapshots).  Is this
possible?
> If not, does anyone have any scripts where it can be done from a host?
> 
> TIA,
>
> Daniel

Any reason you can't use the "snap sched" command for this?

snap sched volname 0 3 0

This takes a snapshot at midnight and keeps at most 3.

If midnight isn't suitable you can configure the hourly
option to take one hourly per day and keep 3.  Suppose you
want 18:00

snap sched volname 0 0 3@18




Steve Losen   scl@virginia.edu    phone: 434-924-0640

University of Virginia               ITC Unix Support




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