UPDATE: I found the solution there: http://www.linuxfoundation.org/collaborate/workgroups/networking/bridge#No_traffic_gets_trough_.28except_ARP_and_STP.29 # cd /proc/sys/net/bridge # ls bridge-nf-call-arptables bridge-nf-call-iptables bridge-nf-call-ip6tables bridge-nf-filter-vlan-tagged # for f in bridge-nf-*; do echo 0 $f; done But I'd like to have expert opinions on this: is it safe to disable all bridge-nf-*? What are they here for? END OF UPDATE I need to bridge LXC containers to the physical interface (eth0) of my host, reading numerous tutorials, documents and blog posts on the subject. I need the containers to have their own public IP (which I've previously done KVM/libvirt). After two days of searching and trying, I still can't make it work with LXC containers. The host runs a freshly installed Ubuntu Server Quantal (12.10) with only libvirt (which I'm not using here) and lxc installed. I created the containers with : lxc-create -t ubuntu -n mycontainer So they also run Ubuntu 12.10. Content of /var/lib/lxc/mycontainer/config is: lxc.utsname = mycontainer lxc.mount = /var/lib/lxc/test/fstab lxc.rootfs = /var/lib/lxc/test/rootfs lxc.network.type = veth lxc.network.flags = up lxc.network.link = br0 lxc.network.name = eth0 lxc.network.veth.pair = vethmycontainer lxc.network.ipv4 = 179.43.46.233 lxc.network.hwaddr= 02:00:00:86:5b:11 lxc.devttydir = lxc lxc.tty = 4 lxc.pts = 1024 lxc.arch = amd64 lxc.cap.drop = sys_module mac_admin mac_override lxc.pivotdir = lxc_putold # uncomment the next line to run the container unconfined: #lxc.aa_profile = unconfined lxc.cgroup.devices.deny = a # Allow any mknod (but not using the node) lxc.cgroup.devices.allow = c *:* m lxc.cgroup.devices.allow = b *:* m # /dev/null and zero lxc.cgroup.devices.allow = c 1:3 rwm lxc.cgroup.devices.allow = c 1:5 rwm # consoles lxc.cgroup.devices.allow = c 5:1 rwm lxc.cgroup.devices.allow = c 5:0 rwm #lxc.cgroup.devices.allow = c 4:0 rwm #lxc.cgroup.devices.allow = c 4:1 rwm # /dev/{,u}random lxc.cgroup.devices.allow = c 1:9 rwm lxc.cgroup.devices.allow = c 1:8 rwm lxc.cgroup.devices.allow = c 136:* rwm lxc.cgroup.devices.allow = c 5:2 rwm # rtc lxc.cgroup.devices.allow = c 254:0 rwm #fuse lxc.cgroup.devices.allow = c 10:229 rwm #tun lxc.cgroup.devices.allow = c 10:200 rwm #full lxc.cgroup.devices.allow = c 1:7 rwm #hpet lxc.cgroup.devices.allow = c 10:228 rwm #kvm lxc.cgroup.devices.allow = c 10:232 rwm Then I changed my host /etc/network/interfaces to: auto lo iface lo inet loopback auto br0 iface br0 inet static bridge_ports eth0 bridge_fd 0 address 92.281.86.226 netmask 255.255.255.0 network 92.281.86.0 broadcast 92.281.86.255 gateway 92.281.86.254 dns-nameservers 213.186.33.99 dns-search ovh.net When I try command line configuration ("brctl addif", "ifconfig eth0", etc.) my remote host becomes inaccessible and I have to hard reboot it. I changed the content of /var/lib/lxc/mycontainer/rootfs/etc/network/interfaces to: auto lo iface lo inet loopback auto eth0 iface eth0 inet static address 179.43.46.233 netmask 255.255.255.255 broadcast 178.33.40.233 gateway 92.281.86.254 It takes several minutes for mycontainer to start (lxc-start -n mycontainer). I tried replacing gateway 92.281.86.254 by : post-up route add 92.281.86.254 dev eth0 post-up route add default gw 92.281.86.254 post-down route del 92.281.86.254 dev eth0 post-down route del default gw 92.281.86.254 My container then starts instantly. But whatever configuration I set in /var/lib/lxc/mycontainer/rootfs/etc/network/interfaces, I cannot ping from mycontainer to any IP (including the host's) : ubuntu@mycontainer:~$ ping 92.281.86.226 PING 92.281.86.226 (92.281.86.226) 56(84) bytes of data. ^C --- 92.281.86.226 ping statistics --- 6 packets transmitted, 0 received, 100% packet loss, time 5031ms And my host cannot ping the container: root@host:~# ping 179.43.46.233 PING 179.43.46.233 (179.43.46.233) 56(84) bytes of data. ^C --- 179.43.46.233 ping statistics --- 5 packets transmitted, 0 received, 100% packet loss, time 4000ms My container's ifconfig: ubuntu@mycontainer:~$ ifconfig eth0 Link encap:Ethernet HWaddr 02:00:00:86:5b:11 inet addr:179.43.46.233 Bcast:255.255.255.255 Mask:0.0.0.0 inet6 addr: fe80::ff:fe79:5a31/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:64 errors:0 dropped:6 overruns:0 frame:0 TX packets:54 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4070 (4.0 KB) TX bytes:4168 (4.1 KB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:32 errors:0 dropped:0 overruns:0 frame:0 TX packets:32 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2496 (2.4 KB) TX bytes:2496 (2.4 KB) My host's ifconfig: root@host:~# ifconfig br0 Link encap:Ethernet HWaddr 4c:72:b9:43:65:2b inet addr:92.281.86.226 Bcast:91.121.67.255 Mask:255.255.255.0 inet6 addr: fe80::4e72:b9ff:fe43:652b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:1453 errors:0 dropped:18 overruns:0 frame:0 TX packets:1630 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:145125 (145.1 KB) TX bytes:299943 (299.9 KB) eth0 Link encap:Ethernet HWaddr 4c:72:b9:43:65:2b UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:3178 errors:0 dropped:0 overruns:0 frame:0 TX packets:1637 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:298263 (298.2 KB) TX bytes:309167 (309.1 KB) Interrupt:20 Memory:fe500000-fe520000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:6 errors:0 dropped:0 overruns:0 frame:0 TX packets:6 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:300 (300.0 B) TX bytes:300 (300.0 B) vethtest Link encap:Ethernet HWaddr fe:0d:7f:3e:70:88 inet6 addr: fe80::fc0d:7fff:fe3e:7088/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:54 errors:0 dropped:0 overruns:0 frame:0 TX packets:67 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4168 (4.1 KB) TX bytes:4250 (4.2 KB) virbr0 Link encap:Ethernet HWaddr de:49:c5:66:cf:84 inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) I have disabled lxcbr0 (USE_LXC_BRIDGE="false" in /etc/default/lxc). root@host:~# brctl show bridge name bridge id STP enabled interfaces br0 8000.4c72b943652b no eth0 vethtest I have configured the IP 179.43.46.233 to point to 02:00:00:86:5b:11 in my hosting provider (OVH) config panel. (The IPs in this post are not the real ones.) Thanks for reading this long question! :-) Vianney