Soft RAID won't boot after update [solved]

esh · 2009-12-18 17:12:31

Hi everyone, I broke my system with an upgrade and have realised I have no idea what I'm doing at the ramfs prompt at all. The deal is this:

/dev/sda1 /dev/sdb1 /dev/sdc1 are (were?) RAID1 /boot
/dev/sda2 /dev/sdb2 /dev/sdc2 are RAID1 /swap
/dec/sda3 /dev/sdb3 /dec/sdc3 are RAID5/LVM

I did an -Syu which hadn't been done for quite some time and it updated 432 packages. I noted there was a nasty looking warning about dmraid 1.5 so I set that package BACK to 1.4 to be safe. Unfortunately that didn't work, clearly, as I have encountered the problem I was trying to avoid. It appears to not be able to find any of the /dev/md* devices on boot and I get dumped at the ramfs prompt.

[edit] Specifically I get:
md: Will configure md0 (super-block) from /dev/sda3,/dev/sdb3,/dev/sdc3, below.
md: Loading md0: /dev/sda3
md: open failed - cannot start array /dev/md0
:: Running Hook [raid-partitions]
md: Will configure md0 (super-block) from /dev/sda3,/dev/sdb3,/dev/sdc3, below.
md: Loading md0: /dev/sda3
md: open failed - cannot start array /dev/md0
...
Root device '/dev/mapper/array-root' doesn't exist, attempting to create it

I can mount my drives but I still don't really know what to fix. I tried putting the 1.5 dmraid in. That hasn't helped yet.

Can someone point me some tips in the right direction?

Last edited by esh (2009-12-19 10:01:23)

saharchie · 2009-12-19 06:34:15

You could boot up with an arch cd/img and just load kernel modules and pacman -U mdadm any anything else you want/need.

After that you can assemble your raid partitions, mount them and access your files.

If it is really bad you might have to chroot into your system after you assemble your raid partitions and then fine-tune any hooks and re-run mkinitcpio....

good luck

.:B:. · 2009-12-19 07:35:53

I know that doesn't help in any way, but how long has it been since you updated? And how did you set up mdadm that it broke?

I've had software RAID running on my server for a while and it never broke. The best way to find out is indeed to boot a live CD and assemble your RAID devices manually.

esh · 2009-12-19 10:01:08

Thanks saharchie, the live CD really helped. I can't do mount --bind in the emergency console so I couldn't figure out how to get the devfs remounted inside my chroot, but it seems that wasn't too hard in the live cd.

Also B, it was a year ago in October the system was installed. I haven't updated since then because of Python 2.6 issues with the vast quantity of department software. Yes, I guess that Arch probably wasn't the ideal choice for such a machine, but I do like it so

Anyway I appear to have magically found the issue. I think it is less of a dmraid update problem and more of an Arch update problem (or at least a feature change I was unaware of). The fix was editing /etc/mkinitcpio.conf and removing 'raid' and 'raid-partitions' from HOOKS and replacing it with 'mdadm', I then removed the md=0,... parameters from the kernel line in /boot/grub/menu.lst, and did a grub->root(hd0),setup(hd0,0) then did pacman -U kernel26... to reinstall the kernel which did all the initcpio magic for me, this time everything was found and it went merrily on its way.

.:B:. · 2009-12-19 11:37:33

You can always blacklist the python update . I am still running on bluez 3.x for example.

Arch Linux

#1 2009-12-18 17:12:31

Soft RAID won't boot after update [solved]

#2 2009-12-19 06:34:15

Re: Soft RAID won't boot after update [solved]

#3 2009-12-19 07:35:53

Re: Soft RAID won't boot after update [solved]

#4 2009-12-19 10:01:08

Re: Soft RAID won't boot after update [solved]

#5 2009-12-19 11:37:33

Re: Soft RAID won't boot after update [solved]

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