On Wed, Feb 22, 2012 at 7:58 AM, Bill Maidment <[log in to unmask]> wrote:
> -----Original message-----
> From:   Bill Maidment <[log in to unmask]>
> Sent:   Mon 20-02-2012 17:43
> Subject:        Degraded array issues with SL 6.1 and SL 6.2
> To:     [log in to unmask] <[log in to unmask]>;
>> I have had some issues with the last two kernel releases. When a degraded array
>> event occurs, I am unable to add a new disk back in to the array. This has been
>> reported on Centos 6.1/6.2 and also RHEL 6.2 (see Bug 772926 - dracut unable to
>> boot from a degraded raid1 array). I have found that I need to revert to kernel
>> 2.6.32-131.21.1.el6.x86_64 in order to be able to add the new drive.
>
> The response from RH is as follows:
> 1) If you try to re-add a disk to a running raid1 after having failed it,
> mdadm correctly rejects it as it has no way of knowing which of the disks
> are authoritative. It clearly tells you that in the error message you
> pasted into the bug.
>
> 2) You reported a Scientific Linux bug against Red Hat Enterprise Linux.
> Red Hat does not support Scientific Linux, please report bugs against
> Scientific Linux to the people behind Scientific Linux.
>
> My response is:
> 1) a) It used to work it out. b) No it does not clearly spell it out. c) Why was it not a problem in earlier kernels?
> 2) Is this an SL bug? I think not!

Bug 772926 doesn't have anything about SL. Are you referring to another bug?

In (1) above, are they replying that you can't "--fail", "--remove",
and then "--add" the same disk or that you can't "--fail" and
"--remove" a disk, replace it, and then can't "--add" it because it's
got the same "X"/"XY" in "sdX"/"sdaXY" as the previous, failed disk?