mountroot prompt with error2, when trying to boot from a single drive in a 2-way mirror

Yudi V yudi.tux at
Wed Apr 15 15:33:19 UTC 2015

Hi Fabian,

First, what is the recommended image hosting site.

I don't think your conclusion is right. If you had a look at the
console messages, it looks like the vdev is created but destroyed due
to guid mismatch.

I will repost the images once I know what service to use.

On 4/15/15, Fabian Keil <freebsd-listen at> wrote:
> yudi v <yudi.tux at> wrote:
>> It's not the BIOS settings, I checked. It picks up the other HDD in the
>> mirror and goes through the boot code and then it fails at booting into
>> zfs
>> root pool.
>> The error is:
>> *Trying to mount root from zfs:osysPool/ROOT/default []...
>> *>
>> * Mounting from zfs:osysPool/ROOT/default failed with error 6.*
>>  it is something to do with the guid mismatch for ada2p3 and ada3p3, not
>> sure why it's even trying to compare them as they are the two partitions
>> in
>> the mirror.
>> Please see the below images for the relevant console messages.
>> screen1:
>> screen2:
> Please note that these resources aren't accessible without allowing
> presumably non-free JavaScript from untrustworthy (YMMV) sources.
>> Is anything amiss in the above label info for these two drives?
>> I have used these two drives before for testing and reinstalled the os
>> and
>> recreated the pools.
>> Any suggestions on how to fix this.
> The problem could be the result of a known race condition that will prevent
> the system from booting if the kernel looks for the root pool before its
> vdevs are available. The less disks there are, the "better" the chances
> that
> ZFS "wins" the race.
> The vfs.mountroot.timeout is ignored for ZFS so the kernel only tries once.
> For details and a patch to change this see:
> As a workaround you can add a UFS root file system on a disk that
> doesn't actually exist to vfs.root.mountfrom. It should be the first
> one so you don't hit the spa_namespace_lock deadlock reported in:
> Fabian

Kind regards,

More information about the freebsd-questions mailing list