log -- lxc static ip nat

sudo brctl addbr lxcbr0
sudo ifconfig -a lxcbr0
lxcbr0    Link encap:Ethernet  HWaddr b2:63:51:ae:XX:XX  
          UP BROADCAST RUNNING 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)
sudo ifconfig lxcbr0 10.10.20.1/24 up
sudo ifconfig -a lxcbr0
lxcbr0    Link encap:Ethernet  HWaddr b2:63:51:ae:XX:XX  
          inet addr:10.10.20.1  Bcast:10.10.20.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:38 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 B)  TX bytes:8756 (8.5 KiB)

修改 /var/lib/lxc/mylxc/config:

＃lxc.network.type = empty
lxc.network.type = vnet
lxc.network.link = lxcbr0
lxc.network.flags = up

啟動 lxc-start -n mylxc
這時候，host 的 iface 會多出一個 奇怪名子的 interface，跟 lxcbr0 bound 在一起..
host 上...

sudo ifconfig
lxcbr0    Link encap:Ethernet  HWaddr fe:0f:87:47:XX  
          inet addr:10.10.20.1  Bcast:10.10.20.255  Mask:255.255.255.0
          inet6 addr: fe80::fc83:faff:fe48:5849/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:16 errors:0 dropped:0 overruns:0 frame:0
          TX packets:161 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1072 (1.0 KiB)  TX bytes:27958 (27.3 KiB)

veth3JU39Y Link encap:Ethernet  HWaddr fe:0f:87:47:XX  
          inet6 addr: fe80::fc0f:87ff:fe47:d33f/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:8 errors:0 dropped:0 overruns:0 frame:0
          TX packets:56 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:648 (648.0 B)  TX bytes:6440 (6.2 KiB)

用 brctl 來看...

sudo brctl show
bridge name bridge id  STP enabled interfaces
lxcbr0  8000.fe0f8747d33f no  veth3JU39Y

現在看 lxc ...
mylxc 的 /etc/network/interfaces

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 10.10.20.10
netmask 255.255.255.0

如果不是，改好以後重開機..
ifconfig 看已經是 eth0 10.10.20.10 了，但是用 route -n 看..

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.10.20.0      0.0.0.0         255.255.255.0   U     0      0        0 eth0

沒有 default gateway...
手動設..

route add default gw 10.10.20.1
route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.10.20.1      0.0.0.0         UG    0      0        0 eth0
10.10.20.0      0.0.0.0         255.255.255.0   U     0      0        0 eth0

這時後 ping 10.10.20.1 已經OK