Can You Refresh a Clone on the Fly?

[glporter82]

This is sort of a newbie Nimble question, but here goes…

Our DBAs have a use case (for testing, say) where they make a snapshot of a DB volume, then make a clone of it, write some stuff to it, and then maybe their test is bad.

At that point they would like to be able (leaving everything mounted, connected, etc.) to tell the clone to revert back to the fresh state as if it were just made (abandon all changes) and then do the test again.

They don’t do this all the time, but they do it.

As it is now, we have learned to make the clone, mount the clone, use the clone.  But right now to refresh it, we have to unmount the clone, destroy the clone, make a new clone, mount the new clone, etc.

This would be something like the NetApp "volume restore snapshot" command, which they are used to using. 

https://library.netapp.com/ecmdocs/ECMP1196817/html/volume/snapshot/restore.html

[jherrera126 · Accepted solution]

Greg - I have only tried this in my lab but once you create the clone the first time the clone shows up as a volume.  At that point you can make snapshots on the new clone volume, create a baseline snapshot before you do anything.  If the DBA's want to "restore" back to baseline you have the snapshot.

Let me know if this works.

Happy Hunting!!! ;^)

[apolman45]

Hi Greg,

I think there's a small mismatch in what you're trying to do on Nimble vs Netapp. The answer that Jason has provided is perfect, but will require a dismount and remount. I'm kind of assuming you were using the Netapp as a fileserver (NFS). If that's the case it's really easy from a storage point of view to do a snapshot restore. You just present the old pointers to your host. In a block-based storage device you have a virtual disk drive and we cannot change the contents of the drive without a remount.

The good news is that this process can be easily scripted. I'm sure your Nimble SE can help you with this should you require some pointers.

Thanks,

Arne