ZFS Recovery Tutorials?

[NineFingers]

I've read the documentation regarding volume recovery. I'm curious if there are any tutorials going through various recovery scenarios? I've looked, but haven't found anything...

I've put together my first FreeNAS box, and am in the process of testing. I want to go through some recovery tests myself so that I'm familiar with what can be safely rebuilt, how, times, etc.

Thanks,
Dave

 

[Ericloewe]

There is no recovery for most issues where ZFS stops working. ZFS is designed to stay working and not work if something goes wrong that it can't manage.

If you mean "replacing failed drives where the proper redundancy exists", like a RAIDZ/2/3 or mirror with a dead drive, follow the instructions in the manual, section 6.3.12. Be careful not to accidentally add the new drive as a stripe.
If you're using encryption, be sure to back up every relevant key and passphrase according to the instructions and make sure to follow the procedure for replacing encrypted drives to the letter. People have lost pools because they were slightly careless with encryption.

 

[NineFingers]

I guess I had a semantics problem. ;) Yes, I meant "replacing..." Section 6.3.12 seemed too brief. I guessed there must be more to it, and concluded there must be some tutorials somewhere.

As a side note, I can vouch for the need to follow the instructions closely. I simulated a failure last night, without consulting the documentation first. End result is a pool that is still functioning in a degraded state, but I'm unable to replace the volume. Tonight's test will be with benefit of following the directions!

 

[NineFingers]

Interesting... last night I simply re-booted my FreeNAS box, and suddenly was able to replace the failed drive with a new one (actually the same drive) via the GUI, and all was well. I had I/O speeds of about 250MB/sec during the resilvering, so was quite happy with that. That was quite a nice surprise... and another validation of the choice of ZFS!