Arch Linux

DrNick

Member

Registered: 2008-01-01

Posts: 14

Arch not booting after update due to udev problems

Hi,
since an update yesterday one of my systems won't boot anymore.
I tried several solutions mentioned in the forum with no success:
1) went back to an older kernel
2) uninstalled and reinstalled mkinitcpio, delete and got a new mkinitcpio.conf
and ran mkinitcpio -p kernel26 on the kernel

I had a sort of success by disabling autoloading in rc.conf. Instead of just crashing
as with autoload enabled it went through to the boot prompt. But I couldn't test any further because I had only usb-keyboard available and that didn't work due to some a missing module I guess . I'll try to get my hands on a PS2 keyboard and look how far I can get later.

I think the key to the problem might be that I use JFS for both root and home partition (ext2 for boot). From the error messages before the crash it looks like the computer can't reach the root-device. I tried to add jfs to the modules section of mkinitcpio.conf and ran mkinitcpio -p kernel26 again but no change.

Maybe someone can give me a hint how to get the system up again and fixing the udev problems. This setup did work for the last couple of months so maybe there was some recent change in this regard I overlooked.

I'm using testing repos and thats what might happen at bleeding edge, no complaining . Nevertheless I would be very interested to understand whats happening and how do get the system up again.

Thanks and best regards

tigrmesh

IRC Op

From: Florida, US

Registered: 2007-12-11

Posts: 792

Re: Arch not booting after update due to udev problems

Hi,
udev has changed.  take a look at:
/etc/udev/readme-udev-arch.txt

initscripts has also changed.

You may also need to http://bbs.archlinux.org/viewtopic.php? … 80#p338780

DrNick

Member

Registered: 2008-01-01

Posts: 14

Re: Arch not booting after update due to udev problems

Hi,
thanks for your answer.

I had merged the pacnew-files already. I read through the udev-readme and did the suggested changes (for example in modprobe.conf) but still not able to boot.

If I boot failsafe I can actually read an error message on the screen instead of blanking out:

...
md: raid10 personality registered for level 10
:: Running Hook [filesystems]
:: Loading root filesystem module...
Attempting to create root device '/dev/sda3'
/bin/mknod "dev/root" b 8 3
/init: 1: cannot open /dev/root: No such device or address

and after some more lines

...
kinit: Unable to mount root fs on device dev(8,3)
kinit: init not found
Kernel panic - not syncing: Atempted to kill init

/dev/sda3 is the correct root-device but I have no raid. I have two hdd's (one IDE, one SATA) and one DVD-RAM on IDE as slave, nothing more, nothing less.

If I boot via install-cd I can mount /dev/sda3. Sometimes I have to run fsck first because mount complains about bad superblock but after fsck I can mount without problem although it didn't report any error. I'm confused.

Any ideas?

sen

Member

From: .de

Registered: 2007-02-18

Posts: 151

Website

Re: Arch not booting after update due to udev problems

Was this ever solved? I've got exactly the same problem.

...
:: Running Hook [filesystems]
:: Loading root filesystem module...
Attempting to create root device '/dev/sda3'
/bin/mknod "dev/root" b 8 3
/init: 1: cannot open /dev/root: No such device or address

...
kinit: Unable to mount root fs on device dev(8,3)
kinit: init not found
Kernel panic - not syncing: Atempted to kill init

My root partition is /dev/sda3 as well. I don't know why he looks at dev(8,3) for the root partition....
The funny thing is that it just happens randomly. Sometimes the system boots just fine and sometimes I get this weird problem and have to reset.

If this was solved please tell me what was causing this for you!

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metal

Member

From: Russia,Moscow

Registered: 2006-01-23

Posts: 45

Re: Arch not booting after update due to udev problems

/dev/sda3 and dev(8,3) is the same. It's strange that happen randomly should be stable:) I had similar trouble, but reason was my mistake. I used wrong initrd image for boot. I think, explicit setting of modules in /etc/mkinitcpio.conf can solve it.

sen

Member

From: .de

Registered: 2007-02-18

Posts: 151

Website

Re: Arch not booting after update due to udev problems

Hm ok, my mkinitcpio settings are like this:

HOOKS="base udev autodetect pata scsi sata filesystems"

The root filesystem is on an sata hdd (in the box are 3 sata and 1 ide hdds).
Should I add/remove a module?

Well, that it only happens randomly bugs me the most... pretty weird. Thx for your help!

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Last.fm | deviantART

_Marco_

Member

Registered: 2008-04-21

Posts: 242

Re: Arch not booting after update due to udev problems

@sven probably this isn't related but...
is it possible that you have this problem?
http://bbs.archlinux.org/viewtopic.php? … 58#p373458
do you use UUID in grub/fastb ?
(edit: wrong link )

Last edited by _Marco_ (2008-06-02 15:34:29)

sen

Member

From: .de

Registered: 2007-02-18

Posts: 151

Website

Re: Arch not booting after update due to udev problems

Nope, I don't use UUIDs. I'll try later if it works with them.

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Last.fm | deviantART

rumil

Member

From: Krakow, Poland

Registered: 2007-11-16

Posts: 39

Re: Arch not booting after update due to udev problems

I had a very similar problem and to solve it I had to explicitly set

MODULES="ata_generic pata_amd sata_sil"

in _that_order_ to get all my sata and ata disks properly recognized

metal

Member

From: Russia,Moscow

Registered: 2006-01-23

Posts: 45

Re: Arch not booting after update due to udev problems

Unfortunately, modern kernel has 2 different subsystems for support pata hdd. It makes trouble, so different subsystems have different names for same devises. Old subsystem names devices as hd*, new as sd*. If old subsystem enables first, it names hdd as hda,  but your kernel finds root on sda3. If you write only one module in your mkinitcpio.conf, it  boots and your hdd has same name always. I write in my config:

MODULES="mbcache jbd dock scsi_mod libata ata_piix ext3"

sen

Member

From: .de

Registered: 2007-02-18

Posts: 151

Website

Re: Arch not booting after update due to udev problems

Persistent device naming in the grub menu.lst solved it for me.

If you have more than one sata/scsi or ide disk controller, the order in which they are added is random. This may result in device names like hdX and hdY switching around randomly on each boot. The same goes for sdX and sdY. Persistent naming allows you not to worry about this at all.

This is probably why it worked randomly. ^^

I'd like to thank you all for your kind support!

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Last.fm | deviantART