Usage on debian hosts

This guide assumes you are running wheezy.

Installing lxc

You have to install lxc from jessie, to do this create /etc/sources.list.d/jesse.list with the contents:

deb http://http.debian.net/debian jessie main
deb-src http://http.debian.net/debian jessie main

To pin the lxc package to jesse, create /etc/apt/preference.d/lxc_jessie_pin.pref:

Package: *
Pin: release n=jessie
Pin-Priority: 100

Package: lxc
Pin: release n=jessie
Pin-Priority: 600

Now you can install the packages:

sudo apt-get install lxc redir bridge-utils

You have to add cgroups to /etc/fstab:

none        /sys/fs/cgroup        cgroup        defaults    0    0

The mount it:

sudo mount /sys/fs/cgroup

Network configuration

There are two ways to set this up depending on whether you want you containers on the same network as the host machine or on a private NAT'ed network

Bridging to your host LAN/WAN

NAT

Install dnsmasq:

sudo apt-get install -y dnsmasq

Configure dnsmasq to disable listening on lxc bridge, add the following contents to /etc/dnsmasq.d/lxc:

bind-interfaces
except-interface=lxcbr0

sudo /etc/init.d/dnsmasq restart

Create an init script to configure lxc network in /etc/init.d/lxc-net with the contents:

#!/bin/sh

### BEGIN INIT INFO
# Provides:             lxc-net
# Required-Start:       $syslog $remote_fs lxc
# Required-Stop:        $syslog $remote_fs lxc
# Should-Start:
# Should-Stop:
# Default-Start:        2 3 4 5
# Default-Stop:         0 1 6
# Short-Description:    Linux Containers Network Configuration
# Description:          Linux Containers Network Configuration
# X-Start-Before:
# X-Stop-After:
# X-Interactive:        true
### END INIT INFO

# Taken from ubuntu's lxc-net upstart config and adopted to init script
# original author: Serge Hallyn <[email protected]>

USE_LXC_BRIDGE="false"
LXC_BRIDGE="lxcbr0"
LXC_ADDR="10.0.3.1"
LXC_NETMASK="255.255.255.0"
LXC_NETWORK="10.0.3.0/24"
LXC_DHCP_RANGE="10.0.3.2,10.0.3.254"
LXC_DHCP_MAX="253"
LXC_DHCP_CONFILE=""
varrun="/var/run/lxc"
LXC_DOMAIN=""

. /lib/lsb/init-functions

start() {
	[ -f /etc/default/lxc ] && . /etc/default/lxc

	[ "x$USE_LXC_BRIDGE" = "xtrue" ] || { exit 0; }

	if [ -d /sys/class/net/${LXC_BRIDGE} ]; then
		if [ ! -f ${varrun}/network_up ]; then
			# bridge exists, but we didn't start it
			exit 0;
		fi
		exit 0;
	fi

	cleanup() {
		# dnsmasq failed to start, clean up the bridge
		iptables -t nat -D POSTROUTING -s ${LXC_NETWORK} ! -d ${LXC_NETWORK} -j MASQUERADE || true
		ifconfig ${LXC_BRIDGE} down || true
		brctl delbr ${LXC_BRIDGE} || true
	}

	# set up the lxc network
	brctl addbr ${LXC_BRIDGE} || { echo "Missing bridge support in kernel"; exit 0; }
	echo 1 > /proc/sys/net/ipv4/ip_forward
	mkdir -p ${varrun}
	ifconfig ${LXC_BRIDGE} ${LXC_ADDR} netmask ${LXC_NETMASK} up
	iptables -t nat -A POSTROUTING -s ${LXC_NETWORK} ! -d ${LXC_NETWORK} -j MASQUERADE

	LXC_DOMAIN_ARG=""
	if [ -n "$LXC_DOMAIN" ]; then
		LXC_DOMAIN_ARG="-s $LXC_DOMAIN"
	fi
	dnsmasq $LXC_DOMAIN_ARG -u dnsmasq --strict-order --bind-interfaces --pid-file=${varrun}/dnsmasq.pid --conf-file=${LXC_DHCP_CONFILE} --listen-address ${LXC_ADDR} --dhcp-range ${LXC_DHCP_RANGE} --dhcp-lease-max=${LXC_DHCP_MAX} --dhcp-no-override --except-interface=lo --interface=${LXC_BRIDGE} --dhcp-leasefile=/var/lib/misc/dnsmasq.${LXC_BRIDGE}.leases --dhcp-authoritative || cleanup
	touch ${varrun}/network_up
}

stop() {
	[ -f /etc/default/lxc ] && . /etc/default/lxc
	[ -f "${varrun}/network_up" ] || exit 0;
	# if $LXC_BRIDGE has attached interfaces, don't shut it down
	ls /sys/class/net/${LXC_BRIDGE}/brif/* > /dev/null 2>&1 && exit 0;

	if [ -d /sys/class/net/${LXC_BRIDGE} ]; then
		ifconfig ${LXC_BRIDGE} down
		iptables -t nat -D POSTROUTING -s ${LXC_NETWORK} ! -d ${LXC_NETWORK} -j MASQUERADE || true
		pid=`cat ${varrun}/dnsmasq.pid 2>/dev/null` && kill -9 $pid || true
		rm -f ${varrun}/dnsmasq.pid
		brctl delbr ${LXC_BRIDGE}
	fi
	rm -f ${varrun}/network_up
}

case "${1}" in
	start)
		log_daemon_msg "Starting Linux Containers"

		start
		;;

	stop)
		log_daemon_msg "Stopping Linux Containers"

		stop
		;;

	restart|force-reload)
		log_daemon_msg "Restarting Linux Containers"

		stop
		start
		;;
esac

sudo chmod +x /etc/init.d/lxc-net
sudo update-rc.d lxc-net start
sudo /etc/init.d/lxc-net start