Re: mdadm array not found on reboot

[Justin Piszcz <jpiszcz@lucidpixels.com>]

On Mon, 7 May 2007, Jeffrey B. Layton wrote:

> Hello,
>
> I apologize if this is a FAQ question or a typical newbie question,
> but by google efforts have yielded anything yet.
>
> I built a RAID-1 using mdadm (Centos 4.2 with 2.6.16.19 kernel
> and mdadm 1.6.0-2). It's just two SATA drives that I created using:
>
> mdadm --create --verbose /dev/md1 --level=raid1 --raid-devices=2 /dev/sda1 
> /dev/sdb1
>
> The md built correctly and I built an ext3 on it. I created /etc/mdadm.conf
> and modified /etc/fstab to mount the device. But when I reboot, the kernel
> drops into RAID repair mode because it can't seem to find /dev/md1 and
> yells about not finding any valid superblock (I can get the exact message
> if needed). However I can mount /dev/sda1 with no problems.
>
> The only way I can get md1 back is to issue the command:
>
> mdadm -A /dev/md1 /dev/sda1 /dev/sdb1
>
> and everything works. I want to have /dev/md1 mounted automatically
> on boot. I'm missing something simple here - how do I do this?
>
> TIA!
>
> Jeff
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

Sounds like a udev issue and/or you did not create the mdadm.conf 
properly.  Show us your mdadm.conf.