8.04 > 8.10 server upgrade 2.6.27-7 kernel refuses to mount LVM root

**djamu** · November 15th, 2008

the 2.6.27-7-server kernel refuses to mount my LVM root after upgrade
> booting previous 2.6.24-21-server just works fine ......

booting the new kernel just gives me following after initramfs initialization ... >

Code:

reading al physical volumes. This may take a while
Begin: waiting for root file sytem

reading al physical volumes. This may take a while
Begin: waiting for root file sytem

reading al physical volumes. This may take a while
Begin: waiting for root file sytem

etc...

seems he's unable to find the root ...

anyone ?

**Philio** · November 16th, 2008

You should be able to boot the old 8.04 kernels and check the grub config. If these won't boot then you'll probably need to boot from a disk/live CD.

**djamu** · November 16th, 2008

yeah thx,

but as I said I can boot from 2.6.24-21-server kernel ( 8.04.1 )..

my grub settings are the same for all kernels ... just to rule that out
LVM uses device-mapper ( so no UUIDS )...
my guess there's something wrong with that ( the device mapper )...
I imaged the partition to a vmware machine, .. still same problem ..
( so without all the raid arrays > production server I won't take it offline )

tried depmodding + a new initramfs too nada .. I'm currently checking, & rebuilding a kernel to see if device-mapper was accidentally removed as a kernel module .. so far that seems ok ...

anyone pretty please ?

**madtom1999** · November 16th, 2008

I've had this on 3 machines I upgraded and the solution appears to be to modify /boot/grub/menu.lst
and add for the current kernel stanza (the line starting kernel)
rootdelay=90

This has worked for me but booting is a bit slow so I guess you can reduce the 90 until it stops working, and go back.

**djamu** · November 16th, 2008

mmm sorry

nope that didn't work, tried even higher settings ( rootdelay=180 )

I'm kind of sure it has something to do with the device-mapper, I did notice ( the rig has a whole bunch of hd's, mostly sata's ) that the 2 PATA's on a PCI card previously as /dev/hd[cd] are now labeled as /dev/sd[cd].. but these aren't the boot disks ... I still need to investigate whether there's another shift in names ... unfortunately booting ( the new kernel ) isn't getting very far ......