TrueNas Pool Degraded after disk replacement


My TrueNas Pool RAIDZ1 has 10 disks, each 2TB. Drive ada4 started to fail and I offline it, shutdown the server, replaced the disk, turned it on, selected “Replace” under the new drive and selected ada4. TrueNas started to resilver the pool, but at the end of the process all the drives are now in status “Degraded”. I scrubbed the pool a few times, nothing changed. Trying to put them back online one by one doesn’t work.

How can I bring my pool back online? any help will be very much appreciated.



If the scrub completed without errors then zpool clear PoolName from the command line might fix that.

Hi Tom,

Thanks a lot for your guidance. It took me a few more steps, but it now works.

Switching to the command line allowed me to access more debugging information, and doing a:

#zpool status -v

Gave me the information I was missing on the GUI. In my case:

errors: Permanent errors have been detected in the following files:

Pool1/Time Machine/xxxxx@aapltm-1689348273:/xxxxx.sparsebundle/bands/1576

Since I didn’t care about my Time Machine (I have another one as a backup), I deleted it, then run a:

#zpool scrub Pool1

And this time it completed with no data errors, although I was a bit worried by the “too many errors” messages.

        NAME                                            STATE     READ WRITE CKSUM
        Pool1                                           DEGRADED     0     0     0
          raidz1-0                                      DEGRADED     0     0     0
            gptid/b470af02-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors
            gptid/b47c05d6-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors
            gptid/b499b444-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors
            gptid/0bf56f9e-2594-11ee-bb58-1c6f653f7f89  DEGRADED     0     0   674  too many errors
            gptid/b483569c-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors
            gptid/b4ae575d-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors
            gptid/b44abcb0-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0 1.38K  too many errors
            gptid/b4a22fb0-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors
            gptid/b47595cc-7867-11ed-b9ef-001b21b3bbe2  DEGRADED     0     0   674  too many errors

errors: No known data errors

I decided to follow your advice, no errors, run a zpool clear:

#zpool clear Pool1
#zpool status -v

        NAME                                            STATE     READ WRITE CKSUM
        Pool1                                           ONLINE       0     0     0
          raidz1-0                                      ONLINE       0     0     0
            gptid/b470af02-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/b47c05d6-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/b499b444-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/0bf56f9e-2594-11ee-bb58-1c6f653f7f89  ONLINE       0     0     0
            gptid/b483569c-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/b4ae575d-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/b44abcb0-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/b4a22fb0-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0
            gptid/b47595cc-7867-11ed-b9ef-001b21b3bbe2  ONLINE       0     0     0

errors: No known data errors

Voila, all good :slight_smile:

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