On Mon, 28 Jul 2008 13:00:19 +0200 "Nils Vogels" bacardicoke@gmail.com wrote:
On Mon, Jul 28, 2008 at 12:08 PM, Simon Vallet svallet@genoscope.cns.fr wrote:
Ideally, we would use SnapMirror to copy the data on the new filer and then transparently (for clients) switch the production system, similarly to what happens when a cluster member fails over to the other member. But we don't know if this is possible.
So the questions are:
- do you think such a procedure could be successful ?
- do you have any other ideas to migrate the data without service
interruption ?
I've done this a dozen times, and it's succesfull, however not entirely without downtime. When switching over, you will need to do a last mirror update to catch the last changes with CIFS disabled on the source filer, this usually means a few seconds per volume of downtime and a few hickups when reconfiguring the paths to CIFS shares.
CIFS is not really critical here, so that wouldn't be much of a problem. As for NFS, could you be a bit more specific about the way clients are migrated ?
If you want me to, I could write you down the basic steps you take to be sure that you will not lose any client data.
I'd very much like that :-)
Just for the sake of the discussion, another poster suggested off-list to simply replace the heads one by one, which seems a quite appropriate solution -- but as the new system is already racked and cabled, it would probably involve too much moving around and re-cabling, which I'm not very keen about.
Without any interruption, we usually use HSM-like configurations such as Acopia (now F5) and the likes have.
We don't really have the need for such an high-availability setup here, but those look quite nice to me.
Thanks to all of you once again -- this list rocks :-)
Simon