Disk used in two pools that are mirrored failed, how to replace disks and recover mirrors for the pools

TrueNAS General
1

Looking for help on how best to do this.

I have a 500GB SSD that is split between two pools. One is for the OS/Boot Pool and the other pool is for SSD storage - Mainly for apps / Use Scale

Both pools were mirrored on a 2nd 500GB SSD

One of the drives took a crap, so I detached the disk from both those pools, so no longer mirrored. I added the new disk but now I need to somehow partition it for two pools and then mirror them again.

So what’s the best process or is it not even possible? I already took a config backup in case the other drive takes a crap.

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Can’t you use the same guide you followed to create this setup from the very start?

Since what you did is unsupported, I would go as far as to say it’s outright discouraged, you will find no official documentation related to your current predicament.

Hopefully you have a backup somewhere else.

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There is almost no point in mirroring the boot disk - a config backup on a regular basis, not stored on the NAS itself is more than adaquate unless you are looking for 5*9’s reliability. (in which case you are doing this the wrong way)

Also what you are doing is unsupported, even to the point of specifically recomended against.

I would hope that no one will help you do this. Basically you are on your own here

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Hi, I agree with the other replies.
Don’t do this setup with using partitions als part of vdevs, only the entire drives.

But if your data that you have on this , still working drive, that are valuable for you and worth the effort of trying to recover, or just as a lesson how you can help yourself in this situation, here some things I would do:

  1. Make a copy of the working drive, with “dd” or something else that is making a image file. Bit by bit!
  2. Use this Image file to work with.
  3. Investigate the partitioning in this image file, by mounting it as a device on a different computer. Note all partitions, start end end of each one, types … What ever information that would help you, to make a similar drive with this partitions. They will have to be the same on your new replacement drive that you probably want to make.
  4. Simple writing this image on a new drive will not work in Truenas, because all of the IDs in the partitioning table will be the same.
  5. Make the partitions on the new drive and pury to the gods that Truenas is happy with the new drive.

Or

Use a new or a drive that you have for your boot pool. Or 2 as a mirror.
Use a new or a drive that you have for your other pool. Or 2 as a mirror.

I totally get it. I also was in this situation that I wanted to use the free space on the boot device. But if you think wice about it. Keep it simple. So I used 1 drive for boot pool and 1 drive for the data and made backups regularly, Truenas makes it simple for you to make replication tasks regularly.

That’s all what I have to say about this situation.
Good luck.