RHEL to FreeBSD file server

[Garrett Cooper]

On Nov 13, 2012, at 7:56 AM, Miroslav Lachman <000.fbsd at quip.cz> wrote:

> Jason Keltz wrote:
> [...]
> 
>> Presently, with the mirrors, I'm using 22 disks with leaving 2 hot spares.
>> If I used 6 x 4 disk vdevs, I use all the disks and don't have hot
>> spares (though I have better redundancy) -- I could put spares into the
>> R720 head which actually has 14 disk slots empty, but I'm hesitant to
>> put a spare for the md1220 using a different driver in the head of the
>> R720...
> 
> Beware of hot spares - they are not "hot".
> 
> kern/134491: [zfs] Hot spares are rather cold...
> http://www.freebsd.org/cgi/query-pr.cgi?pr=134491
> 
> This is long standing unsolved issue. You can add drives as "hot spares" to the zpool, but FreeBSD lacks daemon to recieve notifications about disk failure and failed drive will not be replaced by spare.

You should be able to work around this on 9.1 with a zfs scrub once the drive has been pulled from the chassis, but I recommend testing this out first, just to be safe.
Cheers,
-Garrett