I just started to experiment with LXC containers. I was able to create a container and start it up but I cannot get dhcp to assign the container an IP address. If I assign a static address the container can ping the host IP but not outside the host IP. The host is CentOS 6.5 and the guest is Ubuntu 14.04LTS. I used the template downloaded by lxc-create -t download -n cn-01 command. If I am trying to get an IP address on the same subnet as the host I don't believe I should need the IP tables rule for masquerading but I added it anyways. Same with IP forwarding. I compiled LXC by hand from the following source https://linuxcontainers.org/downloads/lxc-1.0.4.tar.gz Host Operating System Version #> cat /etc/redhat-release CentOS release 6.5 (Final) #> uname -a Linux localhost.localdomain 2.6.32-431.20.3.el6.x86_64 #1 SMP Thu Jun 19 21:14:45 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux Container Config #> cat /usr/local/var/lib/lxc/cn-01/config # Template used to create this container: /usr/local/share/lxc/templates/lxc-download # Parameters passed to the template: # For additional config options, please look at lxc.container.conf(5) # Distribution configuration lxc.include = /usr/local/share/lxc/config/ubuntu.common.conf lxc.arch = x86_64 # Container specific configuration lxc.rootfs = /usr/local/var/lib/lxc/cn-01/rootfs lxc.utsname = cn-01 # Network configuration lxc.network.type = veth lxc.network.flags = up lxc.network.link = br0 LXC default.confu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:12:30:f2 brd ff:ff:ff:ff:f #> cat /usr/local/etc/lxc/default.conf lxc.network.type = veth lxc.network.link = br0 lxc.network.flags = up #> lxc-checkconfig Kernel configuration not found at /proc/config.gz; searching... Kernel configuration found at /boot/config-2.6.32-431.20.3.el6.x86_64 --- Namespaces --- Namespaces: enabled Utsname namespace: enabled Ipc namespace: enabled Pid namespace: enabled User namespace: enabled Network namespace: enabled Multiple /dev/pts instances: enabled --- Control groups --- Cgroup: enabled Cgroup namespace: enabled Cgroup device: enabled Cgroup sched: enabled Cgroup cpu account: enabled Cgroup memory controller: /usr/local/bin/lxc-checkconfig: line 103: [: too many arguments enabled Cgroup cpuset: enabled --- Misc --- Veth pair device: enabled Macvlan: enabled Vlan: enabled File capabilities: /usr/local/bin/lxc-checkconfig: line 118: [: -gt: unary operator expected Note : Before booting a new kernel, you can check its configuration usage : CONFIG=/path/to/config /usr/local/bin/lxc-checkconfig Network Config (HOST) #> cat /etc/sysconfig/network-scripts/ifcfg-br0 DEVICE=br0 TYPE=Bridge BOOTPROTO=dhcp ONBOOT=yes #> cat /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 ONBOOT=yes TYPE=Ethernet IPV6INIT=no USERCTL=no BRIDGE=br0 #> cat /etc/networks default 0.0.0.0 loopback 127.0.0.0 link-local 169.254.0.0 #> ip a s 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:12:30:f2 brd ff:ff:ff:ff:ff:ff inet6 fe80::20c:29ff:fe12:30f2/64 scope link valid_lft forever preferred_lft forever 3: pan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN link/ether 42:7e:43:b3:61:c5 brd ff:ff:ff:ff:ff:ff 4: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN link/ether 00:0c:29:12:30:f2 brd ff:ff:ff:ff:ff:ff inet 10.60.70.121/24 brd 10.60.70.255 scope global br0 inet6 fe80::20c:29ff:fe12:30f2/64 scope link valid_lft forever preferred_lft forever 12: vethT6BGL2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether fe:a1:69:af:50:17 brd ff:ff:ff:ff:ff:ff inet6 fe80::fca1:69ff:feaf:5017/64 scope link valid_lft forever preferred_lft forever #> brctl show bridge name bridge id STP enabled interfaces br0 8000.000c291230f2 no eth0 vethT6BGL2 pan0 8000.000000000000 no #> cat /proc/sys/net/ipv4/ip_forward 1 # Generated by iptables-save v1.4.7 on Fri Jul 11 15:11:36 2014 *nat :PREROUTING ACCEPT [34:6287] :POSTROUTING ACCEPT [0:0] :OUTPUT ACCEPT [0:0] -A POSTROUTING -o eth0 -j MASQUERADE COMMIT # Completed on Fri Jul 11 15:11:36 2014 Network Config (Container) #> cat /etc/network/interfaces # This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). # The loopback network interface auto lo iface lo inet loopback auto eth0 iface eth0 inet dhcp #> ip a s 11: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 02:69:fb:42:ee:d7 brd ff:ff:ff:ff:ff:ff inet6 fe80::69:fbff:fe42:eed7/64 scope link valid_lft forever preferred_lft forever 13: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever