Creating Boot Mirror Fails

TrueNAS General
1

Using Scale 25.04.2.4

I had a drive fail on my boot pool mirror, so I physically replaced it with a new drive. I was unable to replace the failed drive through the GUI (got an error about a vdev not being available), so I removed it through the CLI (zpool detach).

Now I have a boot pool that consists of one drive (the working one) and a new replacement drive that is currently not assigned to anything.

When I try to attach that new drive to the boot pool using the GUI, I get an error that 3-way mirrors are not allowed, however the GUI and the CLI both show that the boot pool only has ONE drive, so the GUI must get the information about what drives are in the pool from somewhere else…

But when I add it through the CLI, the disk is added with a different partition setup than the other one (the other one has two partitions, one of which is in the pool), so I assume that adding it through the GUI does more than just a zpool attach…

I don’t want to reboot the machine with a somewhat iffy boot-pool if I can avoid it… anything I can do to convince the GUI that it is currently only one drive?

2 
root@zurich[~]# zpool status boot-pool
  pool: boot-pool
 state: ONLINE
config:
        NAME                                                STATE     READ WRITE CKSUM
        boot-pool                                           ONLINE       0     0     0
          ata-INTEL_SSDSC2KB960GZ_BTYI339303LJ960CGN-part2  ONLINE       0     0     0
3

Easiest would be to download your System Configuration, reinstall TrueNAS on the boot disks and upload your configuration.