HAST with broken HDD

[George Kontostanos]

On Wed, Oct 1, 2014 at 3:49 PM, InterNetX - Juergen Gotteswinter <
jg at internetx.com> wrote:

> Am 01.10.2014 um 14:28 schrieb George Kontostanos:
> >
> > On Wed, Oct 1, 2014 at 1:55 PM, InterNetX - Juergen Gotteswinter
> > <jg at internetx.com <mailto:jg at internetx.com>> wrote:
> >
> >     Am 01.10.2014 um 10:54 schrieb JF-Bogaerts:
> >     >    Hello,
> >     >    I'm preparing a HA NAS solution using HAST.
> >     >    I'm wondering what will happen if one of disks of the primary
> node will
> >     >    fail or become erratic.
> >     >
> >     >    Thx,
> >     >    Jean-François Bogaerts
> >
> >     nothing. if you are using zfs on top of hast zfs wont even take
> notice
> >     about the disk failure.
> >
> >     as long as the write operation was sucessfull on one of the 2 nodes,
> >     hast doesnt notify the ontop layers about io errors.
> >
> >     interesting concept, took me some time to deal with this.
> >
> >
> > Are you saying that the pool will appear to be optimal even with a bad
> > drive?
> >
> >
>
> https://forums.freebsd.org/viewtopic.php?&t=24786
>


It appears that this is actually the case. And it is very disturbing,
meaning that a drive failure goes unnoticed. In my case I completely
removed the second disk on the primary node and a zpool status showed
absolutely no problem. Scrubbing the pool began resilvering which indicates
that there is actually something wrong!

   pool: tank

 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 16K in 0h2m with 7 errors on Wed Oct  1 16:00:47 2014

config:


 NAME            STATE     READ WRITE CKSUM

tank            ONLINE       0     0     7

  mirror-0      ONLINE       0     0    40

    hast/disk1  ONLINE       0     0    40

    hast/disk2  ONLINE       0     0    40


Unfortunately, in this case there was data loss and hastctl status does not
report the missing disk!

Name Status Role Components

disk1 complete primary        /dev/ada1 hast2

disk2 complete primary        /dev/ada2 hast2

-- 
George Kontostanos
---
http://www.aisecure.net