a strange and terrible saga of the cursed iSCSI ZFS SAN

[Eugene M. Zheganin]

Hi,

On 05.08.2017 22:08, Eugene M. Zheganin wrote:
>
>   pool: userdata
>  state: ONLINE
> status: One or more devices has experienced an error resulting in data
>         corruption.  Applications may be affected.
> action: Restore the file in question if possible.  Otherwise restore the
>         entire pool from backup.
>    see: http://illumos.org/msg/ZFS-8000-8A
>   scan: none requested
> config:
>
>         NAME               STATE     READ WRITE CKSUM
>         userdata           ONLINE       0     0  216K
>           mirror-0         ONLINE       0     0  432K
>             gpt/userdata0  ONLINE       0     0  432K
>             gpt/userdata1  ONLINE       0     0  432K
That would be funny, if not that sad, but while writing this message, 
the pool started to look like below (I just asked zpool status twice in 
a row, comparing to what it was):

[root at san1:~]# zpool status userdata
   pool: userdata
  state: ONLINE
status: One or more devices has experienced an error resulting in data
         corruption.  Applications may be affected.
action: Restore the file in question if possible.  Otherwise restore the
         entire pool from backup.
    see: http://illumos.org/msg/ZFS-8000-8A
   scan: none requested
config:

         NAME               STATE     READ WRITE CKSUM
         userdata           ONLINE       0     0  728K
           mirror-0         ONLINE       0     0 1,42M
             gpt/userdata0  ONLINE       0     0 1,42M
             gpt/userdata1  ONLINE       0     0 1,42M

errors: 4 data errors, use '-v' for a list
[root at san1:~]# zpool status userdata
   pool: userdata
  state: ONLINE
status: One or more devices has experienced an error resulting in data
         corruption.  Applications may be affected.
action: Restore the file in question if possible.  Otherwise restore the
         entire pool from backup.
    see: http://illumos.org/msg/ZFS-8000-8A
   scan: none requested
config:

         NAME               STATE     READ WRITE CKSUM
         userdata           ONLINE       0     0  730K
           mirror-0         ONLINE       0     0 1,43M
             gpt/userdata0  ONLINE       0     0 1,43M
             gpt/userdata1  ONLINE       0     0 1,43M

errors: 4 data errors, use '-v' for a list

So, you see, the error rate is like speed of light. And I'm not sure if 
the data access rate is that enormous, looks like they are increasing on 
their own.
So may be someone have an idea on what this really means.

Thanks.
Eugene.