Re: ZFS errors with two HEX numbers.

From: Miroslav Lachman <000.fbsd_at_quip.cz>
Date: Sat, 25 Sep 2021 22:00:59 UTC 
On 25/09/2021 21:28, Zaphod Beeblebrox wrote:
> I've got a ZFS pool --- 3 x 8 x 4T disks in a RAIDZ2 configuration.  Every
> few months I scrub them.  This time, curiously, it came up with an error.
> All the disks in a vdev simultaneously give an error when this is
> scanned.... thusly:
> 
>            raidz2-3      ONLINE       0     0     0
>              gpt/v1-f0   ONLINE       0     0     1
>              gpt/v1-f1   ONLINE       0     0     1
>              gpt/v1-f2   ONLINE       0     0     1
>              gpt/v1-f3   ONLINE       0     0     1
>              gpt/v1-f4   ONLINE       0     0     1
>              gpt/v1-f5   ONLINE       0     0     1
>              gpt/v1-f6a  ONLINE       0     0     1
>              gpt/v1-f7b  ONLINE       0     0     1
> 
> ... and if I add -v to the status, I see the following right now:
> 
> errors: Permanent errors have been detected in the following files:
>          <0x57b2>:<0x73ab46>
> 
> Now... since that happened, I have scrubbed twice more.  The first number
> changes each time.  Last scrub it was: <0x4223>:<0x73ab46>.  Note the last
> number is not changing.
> 
> I have done some googling and found that this might be something that got
> corrupted on delete or somesuch.  My OCD would like to know what 0x4223
> maps to (or now 0x57b2) s.t. I could find it and remove it.  I _think_ this
> is a snapshot reference?

I have seen this in the past. It was corruption on some deleted file 
preserved on snapshot. Once I deleted snapshots this error disappeared.

[...]

Miroslav Lachman