Snapshots on an HP Storageworks EVA4000 SAN. Our general processing works like this:
1. Stop application server (with file system on SAN)
2. Stop Oracle DB (with data, archive logs, redo logs and application on SAN)
3. Unmount all of the above mention file systems (they are striped at the OS level to pull off load balancing over dual fiber paths, so there are double the LUNs on the SAN)
4. Make snapshots of all the LUNs
5. Mount, start up Oracle DB and Application server again
That's a rough approximation of what we used to do on the old SAN, now that we've moved to the EVA4000 I'm rebuilding things, so it occurred to me that we might be able to cut the downtime way down if we could either snapshot while the systems are still up. Someone suggested that Oracle hot backup mode would allow this on the Oracle side. The app server side is really where our biggest hit in downtime comes from since shutdown and startup of the services can take 10-12 minutes in total.
On the HP ITRC forums I was told pretty much that it seems like we're stuck because of the way the app server is designed (not my call to judge that and we don't own the code). So my thoughts now are to do a multisnap of all the LUNs with Oracle in hot backup mode briefly, and while the application server is up but at a time when it's likely to not be busy. Then just accept the fact that I'll need to run an fsck on the snapshotted file systems since they're still mounted when I snap them.
I'm still testing and have run into other problems which I will be posting about next. So I think we'll either have to live with the downtime or if making the snapshots while the systems are live but not too busy, we'll have to live with fsck.
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What snapshots are you talking about and who is to do the backup?
But to answer your first question: Not that I know of... you would find that on some workstations (because at inactivity time limit, it dumps the RAM to disk and "pause"s).