Bug#619958: grub update fails on larger number of /dev/sd[a-z]+ devices

[Christian Schwamborn]

Package: grub-common
Version: 1.98+20100804-14
Severity: normal

I recently configured a system for testing purposes with a larger number 
of fc-luns resulting in 320 sd devices (40 luns * 8 paths per lun) plus 
4 sd devices from the servers internal disk system.
When I tried to install a new kernel I got something like this from 
update-grub:

0 root at xen-6:~# update-grub
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-2.6.34.8+dom0.1-xen-amd64
Found initrd image: /boot/initrd.img-2.6.34.8+dom0.1-xen-amd64
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
Found linux image: /boot/vmlinuz-2.6.32-5-xen-amd64
Found initrd image: /boot/initrd.img-2.6.32-5-xen-amd64
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
Found linux image: /boot/vmlinuz-2.6.32-5-amd64
Found initrd image: /boot/initrd.img-2.6.32-5-amd64
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
Found linux image: /boot/vmlinuz-2.6.32-5-xen-amd64
Found initrd image: /boot/initrd.img-2.6.32-5-xen-amd64
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
Found linux image: /boot/vmlinuz-2.6.34.8+dom0.1-xen-amd64
Found initrd image: /boot/initrd.img-2.6.34.8+dom0.1-xen-amd64
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
/usr/sbin/grub-probe: error: cannot find a GRUB drive for /dev/sdli1. 
Check your device.map.
done

update-grub was unwilling to update /boot/grub/grub.cfg, I had to 
disconnect the machine from the fibre channel to complete this task.

Depending on the order the devices are found during the boot process, 
the device of the internal disk system changes and if /dev/sda1 becomes 
/dev/sdli1 grub fails. I think it depends on how many characters the 
device uses.

By the way: My device.map is fine

I'm using Debian Squeeze
kernel linux-image-2.6.32-5-amd64, linux-image-2.6.32-5-xen-amd64 2.6.32-30
libc6 2.11.2-10