This is a small recipe to resize a disk image. In this case I wanted to make it bigger.

create a sparse file :

dd if=/dev/zero of=xen.img bs=1k count=1 seek=30M


copy the old file system to the sparse file:

dd if=old-xen.img of=xen.img conv=notrunc


now we resize the fs (reiserfs in this case)

resize_reiserfs xen.img


and we can happily mount it.

mount -o loop xen.img test/


now we have a bigger fs !

# df -h
Filesystem Size Used Avail Use% Mounted on
/home/xen.img 30G 338M 30G 2% /home/test