zpool degraded - 'UNAVAIL cannot open' functioning drive

[Jeremy Chadwick]

On Wed, Aug 06, 2008 at 10:35:54PM -0700, Vye Wilson wrote:
> I tested it again and it seems I was mistaken in my last email. If the drive
> is removed manually it will _not_ show up in atacontrol.
> 
> atacontrol attach ata3
> atacontrol: ioctl(IOCATAATTACH): File exists
> [root at Touzyoh /home/vye]# atacontrol list
> ATA channel 3:
>     Master:      no device present
>     Slave:       no device present
> [root at Touzyoh /home/vye]# atacontrol detach ata6
> [root at Touzyoh /home/vye]# atacontrol attach ata6
> Master:      no device present
> Slave:       no device present
> 
> I'm not sure what happened the first few times but if I reboot the server
> the device will show up in atacontrol and the zpool will resilver. This
> doesn't seem to be a ZFS problem like I originally thought.

Correct, it's a FreeBSD ATA subsystem/driver problem.

I'm actually amazed your kernel didn't panic when you did the 2nd
attach.  The first attach returning "File exists" doesn't surprise me
either.

I've been following these kinds of issues with ATA for many months now,
so I want you to know that you're not alone.  It is NOT specific to your
nVidia controller either; others see the same thing on Intel ICH, and
VIA.

If you attach those SATA disks to your Areca controller and perform the
exact same tests (you'll need to use camcontrol, of course), I can
almost guarantee you things will behave 100% correctly.

My advice at this point in time, because as of today I have officially
lost faith in it: avoid ata(4) at all costs.

-- 
| 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 |