Hi all
I would appreciate some help. Hopefully the answer is obvious, but I have searched many posts unsuccessfully.
Im a newbie to TrueNas, but I have worked in IT for decades so pickup quickly.
BACKGROUND:
Im looking to move my storage to TrueNAS, but before I do I want to test a few scenarios to ensure I know how to recover before they happen in real life.
One scenario that happened to me previously (not on TrueNAS), was a single disk failing catastrophically and 'disappearing'. I was running hardware RAID1 (2 mirrors) and everything worked as expected. The array showed as degraded, I was able to finish the days work, then perform my backup early (just in case) and finally replace one disk. All good.
I wanted to test similar on TrueNAS. Ive setup a vanilla TrueNAS core instance with a single pool using two mirrored SATA 3TB drives. System is also on this pool. Aside from the boot disk, there are no other disks. All is functioning well.
MY TEST:
With TrueNAS functioning normally, I unplugged the SATA cable from one mirror disk. The pool went to status "Online (unhealthy)". I could still access my data, so all good so far. Next I shutdown the server to simulate removal of the 'failed' drive until a new one was available (I had done this previously as the drive was making noise and getting hot, I didnt want to leave it spinning until a new one arrived. Also aside from my dodgy 'pull the SATA cable' above, I always power down before messing inside - its too easy to make mistakes).
PROBLEM:
On reboot, the TrueNAS array showed status OFFLINE. No access to data on the remaining mirror and no way back. I had expected "Online (unhealthy)" or "Degraded". I have spent a few hours reading posts and trying different things but have got nowhere. FYI reconnecting the unplugged drive returned everything to normal after reboot, but obviously I wouldnt have that option in real life!
What am I missing? After reboot the pool should remain accessible with one good mirror.
Cheers
I would appreciate some help. Hopefully the answer is obvious, but I have searched many posts unsuccessfully.
Im a newbie to TrueNas, but I have worked in IT for decades so pickup quickly.
BACKGROUND:
Im looking to move my storage to TrueNAS, but before I do I want to test a few scenarios to ensure I know how to recover before they happen in real life.
One scenario that happened to me previously (not on TrueNAS), was a single disk failing catastrophically and 'disappearing'. I was running hardware RAID1 (2 mirrors) and everything worked as expected. The array showed as degraded, I was able to finish the days work, then perform my backup early (just in case) and finally replace one disk. All good.
I wanted to test similar on TrueNAS. Ive setup a vanilla TrueNAS core instance with a single pool using two mirrored SATA 3TB drives. System is also on this pool. Aside from the boot disk, there are no other disks. All is functioning well.
MY TEST:
With TrueNAS functioning normally, I unplugged the SATA cable from one mirror disk. The pool went to status "Online (unhealthy)". I could still access my data, so all good so far. Next I shutdown the server to simulate removal of the 'failed' drive until a new one was available (I had done this previously as the drive was making noise and getting hot, I didnt want to leave it spinning until a new one arrived. Also aside from my dodgy 'pull the SATA cable' above, I always power down before messing inside - its too easy to make mistakes).
PROBLEM:
On reboot, the TrueNAS array showed status OFFLINE. No access to data on the remaining mirror and no way back. I had expected "Online (unhealthy)" or "Degraded". I have spent a few hours reading posts and trying different things but have got nowhere. FYI reconnecting the unplugged drive returned everything to normal after reboot, but obviously I wouldnt have that option in real life!
What am I missing? After reboot the pool should remain accessible with one good mirror.
Cheers
