zpool degraded - 'UNAVAIL cannot open' functioning drive

[Jeremy Chadwick]

On Wed, Aug 06, 2008 at 09:09:02PM -0700, Vye Wilson wrote:
> Hello,
> 
> I setup a raidz1 zpool to test ZFS with a device failure and to see how
> quickly the zpool could be resilvered. The system I'm using has a backplane
> that all the drives are connected to, so everything is hotswappable. I
> created the raidz1 zpool and then removed one of the drives. zpool status
> showed that the pool was degraded but online. Ok great, so lets bring the
> now functioning drive back online.
> 
> [root at Touzyoh /home/vye]# zpool online ztemp ad18
> Bringing device ad18 online
> 
> Everything looks good... lets check the zpool status
> 
>   pool: ztemp
>  state: DEGRADED
> status: One or more devices could not be opened.  Sufficient replicas exist
> for
>     the pool to continue functioning in a degraded state.
> action: Attach the missing device and online it using 'zpool online'.
>    see: http://www.sun.com/msg/ZFS-8000-D3
>  scrub: resilver completed with 0 errors on Wed Aug  6 20:59:54 2008
> config:
> 
>     NAME        STATE     READ WRITE CKSUM
>     ztemp       DEGRADED     0     0     0
>       raidz1    DEGRADED     0     0     0
>         ad10    ONLINE       0     0     0
>         ad14    ONLINE       0     0     0
>         ad18    UNAVAIL      0     0     0  cannot open
> 
> errors: No known data errors
> 
> Doh! still degraded. It shows 'UNAVAIL cannot open' I've tried rebooting but
> it will not open that drive at all. According to dmesg the drive is
> functional, and if I destroy the pool and recreate it the drive works fine.
> I wasn't able to find any similar issues on this mailing list or in google.
> Does anyone have any ideas? I've attached my dmesg output.

What was in your dmesg when you yanked the disk?  What was in your dmesg
when you re-inserted the disk?

Did you try detaching it administratively using "atacontrol detach"
first, then retaching it using "atacontrol attach"?

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |