TrueNAS Core 12U8.1

Hi guys,

I have TrueNAS core 12 and had a pool of 2 HDDs in mirror mode. The one of the drives started having problems so I decided to replace it before it failed completely.
I tried to follow the steps in the documentation with the hot spare option: offlined, detached the failing drive etc. I must have missed a step as the new drive is showing under “Spares” if I go to Pools->Status. Moreover, no resilvering process has been initiated. So: Is there anything I can do to add the Spare disk to the Mirror?

You need to remove the spare from the pool
zpool remove <pool name> <device name>
and then replace the failing drive with the new
https://www.truenas.com/docs/files/CORE12.0Docs.pdf 6.4.2 - Replacement

I have a similar scenario. A drive failed and a spare was pulled in and resilvered. I replaced the failed disk (it resilvered again) and now I see this:

          mirror-7                                        ONLINE       0     0     0
            spare-0                                       ONLINE       0     0     0
              gptid/a56eedf5-55ae-11f0-b938-ac1f6bbb987e  ONLINE       0     0     0
              gptid/28839031-d88b-11ed-921e-ac1f6bbbbcc6  ONLINE       0     0     0
            gptid/2dff066d-62ed-11ee-a881-ac1f6bbb987e    ONLINE       0     0     0

and this shows under spares:

 gptid/28839031-d88b-11ed-921e-ac1f6bbbbcc6      INUSE     currently in use

should I just run “zpool remove gptid/28839031-d88b-11ed-921e-ac1f6bbbbcc6” ?