VSM (and therefore SM2T) will preserve inodes, but it will be up to you to preserve the FSID of the original volume on east. If you go into priv set advanced, you will find 'vol read_fsid' and 'vol rewrite_fsid' which can accomplish this. Be aware that Rewriting the fsid requires the volume to be restricted and you will need to rewrite the original one first to something totally different. FSIDs must be unique not only within a controller but within an HA-pair if you want failover to work properly.

While these commands are perfectly safe when used properly, they are guns so point them away from you (i.e. know what you're doing before you it or you could have a disruption you don't want).

-- Adam Fox Systems Engineer adamfox@netapp.com

-----Original Message----- From: John Stoffel [mailto:john.stoffel@taec.toshiba.com] Sent: Monday, December 07, 2009 5:50 PM To: toasters@mathworks.com Subject: Redoing snapmirror to a destination

Guys,

Do to stupidity on my part, I managed to accidently delete a snapshot on the source side of a snapmirror pair, so that snapmirror can't continue. It's not critical, it's just our tools area, which isn't updated frequently.

So now I want to re-snapmirror, but I want to limit the downtime of the clients on the destination side as much as possible when I switch them to the new re-snapmirrored volume.

Currently, my clients mount east:/vol/tools, so what I'd like to do is:

west> snapmirror store tools rst0a,rst1a

east> vol create tools .... east> vol restrict tools east> snapmirror retrieve tools_new rst0a,rst1a

Now for the tricky part:

east> nfs off east> vol rename tools tools_old east> vol rename tools_new tools east> nfs on east> exportfs -a -v

so that all my clients see (on a read-only volume) is a quick outage or pause in NFS traffic, then they just continue on using tools and such as usual.

Or will I be forced to reboot all of my client machines one by one? Which will be truly truly truly painful...

The general snapmirror update and cleanup of the old volume is trivial. It's limiting the outage to my clients that I worry about.

Thanks, John John Stoffel - Senior Staff Systems Administrator - System LSI Group Toshiba America Electronic Components, Inc. - http://www.toshiba.com/taec john.stoffel@taec.toshiba.com - 508-486-1087