Re: Failure to boot after upgrade 14.3->14.4 with "ZFS: unsupported feature: com.klarasystems: vdev_zaps_v2"

On 01/05/2026 13:15, Einar Indridason wrote:
> Is there a way to check a running 14.4 system (upgraded from 14.3) if that
> ZFS filesystem needs to run a "zfs upgrade" ?  Is there some ... "zfs
> show-needs-update"
> 
> Thanks in advance,

Remember that updates can be applied at both zpool and zfs levels.

`zpool upgrade` will show you if there are upgrades to apply to your 
zpools.  Then:

`zpool upgrade -a`

or

`zpool upgrade zpoolname`

will actually apply upgrades, either to all pools or to the named pool.

Similarly:

`zfs upgrade`

will show you if there are any updates to apply at the ZFS level, and then:

`zfs upgrade -a`

will apply upgrades to all ZFSes.  See `zfs-upgrade(8)` for how to 
specify updating selected ZFSes.

Be sure to update boot blocks / EFI as well as updating the zpool, or 
you may be left with an unbootable system.

	Cheers,

	Matthew