Comment 4 for bug 929382

However, in both cases it apparently fails in the same exit path. It seems that the trapping is meant to call undo_network() on failure (which works), then undo_network() goes all the way to the end, and then the script just exits:

.0.3.1 --dhcp-range 10.0.3.2,10.0.3.254 --dhcp-lease-max=253 --dhcp-no-override --except-interface=lo --interface=lxcbr0

dnsmasq: failed to bind listening socket for fe80::188f:6ff:fe83:141: Address already in use
+ undo_network
+ [ -f /var/run/lxc/dnsmasq.pid ]
+ iptables -t nat -D POSTROUTING -s 10.0.3.0/24 -j MASQUERADE
[...]
+ echo * Failed to set up LXC network
 * Failed to set up LXC network
root@ubuntu:~# echo $?
2