Degraded boot pool, any way to check disk in system?

TrueNAS General
1

Hello, got the “degraded pool” warning email this morning for my boot pool, which is a pair of mirrored PNY 256gb NVME SSD’s. One is fine, one is was originally showing as offline, after a system reboot, is now listed as faulted. The drives are 2 years old.

Are there any steps I can take to scan the failed drive while in the system? I don’t have another way to currently read the drive (but just ordered an external shell to USB setup to do so in when it arrives)

In the short term, I backed up my settings just in case, but are there other steps I need to take to ensure I don’t lose anything vital here in case I have issues with the other boot drive before the replacement arrives (again just ordered an offbrand 256gb new drive).

System:

TrueNAS Scale 25.04

Topton Mini NAS board

Celeron N5105

32 Gb of RAM

Boot Pool: Two 256 Gb PNY NVME SSD (Mirrored)

Storage Pool: Three 14TB Seagate Exos Drives (Raid Z1)

2

Download a backup of the system configuration file. On 25.10.1 - Goldeye, it’s under the System, Advanced Settings then a button on upper right for Manage Configuration. As long as you have that, it’s easy to do a reinstall of the boot-pool and upload your config.

You can try running SMART tests on the bad one

3

My second NVME drive isn’t even showing up now - not exactly sure what to do to allow it to run SMART tests.

4

I should clarify, the output of “sudo zpool status” when SSH’d in is the following for my boot pool:

  pool: boot-pool
 state: DEGRADED
status: One or more devices could not be used because the label is missing or
	invalid.  Sufficient replicas exist for the pool to continue
	functioning in a degraded state.
action: Replace the device using 'zpool replace'.
   see: https://openzfs.github.io/openzfs-docs/msg/ZFS-8000-4J
  scan: scrub repaired 0B in 00:01:11 with 0 errors on Tue Jan 13 18:30:51 2026
config:

	NAME                    STATE     READ WRITE CKSUM
	boot-pool               DEGRADED     0     0     0
	  mirror-0              DEGRADED     0     0     0
	    780949030338813621  FAULTED      0     0     0  was /dev/nvme0n1p3
	    nvme0n1p3           ONLINE       0     0     0

errors: No known data errors
5

You can try going to the manufacturer website and see if they have software to tell the status of the NVMe or check it’s health. You listed PNY in first post. You might have to run it from a Windows computer. Look for SSD Toolbox. There are SATA and PCIe versions. It might help with secure erasing too

6

File the drive as dead and remove it or replace it.
Efforts to resurect it will quickly cost more than a new boot device…