ZFS with errors

[Trond Endrestøl]

On Wed, 13 Apr 2016 15:41+0200, Trond Endrestøl wrote:

> On Wed, 13 Apr 2016 14:52+0200, Luciano Mannucci wrote:
> 
> > 
> > Hello all,
> > 
> > I'm testing ZFS, so please forgive me for my dumb questions...
> > I have a pool with a zfs filesystem that shows erors. I tried to get
> > rid of them by removing the files listed by zpool status -v and
> > restoring without seeing anything different.
> > I tried with zpool scrub <mypool> and got only more errors.
> > My situation now is:
> > root at vodka:~ # zpool status -v
> >   pool: expool1
> >  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: scrub repaired 0 in 7h29m with 9 errors on Fri Apr  8 20:09:47 2016
> > config:
> > 
> > 	NAME                                          STATE     READ WRITE CKSUM
> > 	expool1                                       ONLINE       0     0    10
> > 	  gptid/8ccea78c-05ef-4a3a-9502-4106ca736958  ONLINE       0     0     8
> > 	  gptid/864c27ea-ecd2-4cf9-9450-1afad9065fa1  ONLINE       0     0     0
> > 	  diskid/DISK-WD-WCC4M2780110s3               ONLINE       0     0     0
> > 	  diskid/DISK-WD-WCC4M2780110s1               ONLINE       0     0    12
> > 
> > errors: Permanent errors have been detected in the following files:
> > 
> >         expool1/mirrors:<0x600>
> >         /var/spool/mirrors/mageia/distrib/4/x86_64/media/core/release/kde4-style-bespin-icons-0.1-0.1649svn.1.mga4.noarch.rpm
> >         /var/spool/mirrors/mageia/distrib/4/x86_64/media/core/release/lilypond-doc-2.18.0-1.mga4.noarch.rpm
> >         /var/spool/mirrors/mageia/distrib/4/x86_64/media/core/updates/wesnoth-data-1.10.7-2.1.mga4.noarch.rpm
> >         expool1/mirrors:<0x6dba>
> > root at vodka:~ # 
> > 
> > 
> > is there a way to see which "9 errors" did scrub find?
> > what I'm I suposed to do to clear the situation?
> 
> Try:
> 
>   zpool clear expool1
>   zpool scrub expool1
> 
> Let the scrub finish.
> 
> If the same three files reappears, then refetch those files.
> The lines ending with a hexadecimal number represents deleted files, 
> as far as I know.
> 
> Once you have mended your files, run "clear" and "scrub" one more 
> time.

I noticed you have four disks in a striped configuration, aka RAID 0.

There's no redundancy in this pool, making it hard for ZFS to 
automatically repair your files.

Maybe you should destroy your pool and recreate it using a mirrored 
configuration. Maybe, mirror disks 1 & 2, and disks 3 & 4, e.g.

zpool create expool1 mirror gptid/8ccea78c-05ef-4a3a-9502-4106ca736958 gptid/864c27ea-ecd2-4cf9-9450-1afad9065fa1 mirror diskid/DISK-WD-WCC4M2780110s3 diskid/DISK-WD-WCC4M2780110s1
                     ^^^^^^                                                                                       ^^^^^^

Some proper disk labelling and setting the 
kern.geom.label.gptid.enable tunable to 0 in /etc/loader.conf might 
make it easier for you to identify each disk.

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