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I am trying to install virtual machine with this command, but have no success:

vmbuilder kvm ubuntu --verbose --suite precise --flavour virtual \
--part partitions.txt --ip --hostname edb1 --arch amd64 \
-o --libvirt qemu:///system --user someuser --pass somepass \
--raw /home/virtual-machines/edb1.disk1.img \
--raw /home/virtual-machines/edb1.disk2.img \
--domain --mem 4096 --cpus 4

This is the error:

I: Extracting xz-utils...
I: Extracting zlib1g...
W: Failure trying to run: chroot /tmp/tmp_JdKzu mount -t proc proc /proc
, stderr: 

The host kernel is not original but modified by server provider. Why is the chroot needed for installation?

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That's how vmbuilder is designed, as a shortcut to installing the image using the VM, it builds it on disk using a chroot. chroot require root access unless the administrator has made allowances for you.

Try using sudo.

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The problem was with kernel. After I changed the kernel, I was able to create the virtual machine. – Bruce Aug 15 '12 at 10:25

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