Quoting from http://bts.grml.org/grml/issue1166:
| I booted using the options lvm debnet, expecting debnet to use the
| /etc/network/interfaces file from the LVM logical volume. Instead, it
| used the /etc/network/interfaces file from /dev/loop0, because that is
| listed earlier in /proc/partitions.
Thanks: John S. Skogtvedt <jss@bzz.no> for bugreport and patch
exit 0
fi
-DEVICES="$(< /proc/partitions tail -n +3 | awk '{print "/dev/"$4}' | tr "\n" " ")"
+DEVICES="$(< /proc/partitions tail -n +3 | awk '($4 !~ /loop[0-9]+/) {print "/dev/"$4}' | tr "\n" " ")"
DEVICES="$DEVICES $(ls /dev/mapper/*)"
FOUND_DEBNET=""