Comment 16 for bug 576501

Quoting Henrik Bach (<email address hidden>):
> 2011-04-16 04:36:12,380 INFO : Creating config file
> /etc/default/grub with new version
> 2011-04-16 04:36:12,970 INFO : /proc/devices: fopen failed: No such
> file or directory
> 2011-04-16 04:36:12,971 INFO : Is device-mapper driver missing from kernel?

Hm. Actually all the problems I've had I've traced to environments (bad
network setup for one, device permissions for another). I finally got a
maverick xen host in a working environment - and vmbuilder -ec2 worked

What does /proc/devices on your host show? What sort of storage setup
do you have? The 'Is device-mapper driver missing from kernel?' is
odd, and presumably comes from grub in the chroot. It almost sounds
like your host is multipathed. What does 'df -h' and 'mount' on the
host show?

Does a regular 'vmbuilder xen ubuntu' work for you?