在启动容器时指定—net=none，表明在启动的Container中不配置任何网络信息，启动后看到的Container内的信息如下所示：没有eth0接口只有一个lo回环接口。但还是有自己独立的network namespace。
[root@4685a85d0e11
/]# ifconfig
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:65536 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)
docker run -i -t --rm --net=none
frankzfz/centos6.3-base-v1 /bin/bash
[root@0861fd7f405a /]# ifconfig
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:65536 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)
获取容器的进程号，
[root@10-10-63-106 ~]# docker inspect -f
'{{.State.Pid}}' 0861fd7f405a
695
[root@10-10-63-106 ~]# docker inspect -f
'{{.State.Pid}}' 4685a85d0e11
638
创建网络命名空间的跟踪文件
[root@10-10-63-106 ~]# mkdir -p
/var/run/netns
[root@10-10-63-106 ~]# ln -s
/proc/695/ns/net /var/run/netns/695
[root@10-10-63-106 ~]# ln -s
/proc/638/ns/net /var/run/netns/638
创建一对peer接口，A指定为Container_ID=0861fd7f405a的接口名，B指定为Container_ID=4685a85d0e11，并添加路由信息，他们的下一跳都是指向对端IP地址。
[root@10-10-63-106 ~]# ip link add A type
veth peer name B
[root@10-10-63-106 ~]# ip link set A netns
695
[root@10-10-63-106 ~]# ip netns exec 695 ip
addr add 10.1.1.1/32 dev A
[root@10-10-63-106 ~]# ip netns exec 695 ip
link set A up
[root@10-10-63-106 ~]# ip netns exec 695 ip
route add 10.1.1.2/32 dev A
[root@0861fd7f405a /]# ifconfig
A
Link encap:Ethernet HWaddr
CA:39:26:CD:24:BD
inet addr:10.1.1.1 Bcast:0.0.0.0
Mask:255.255.255.255
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:1000
RX bytes:0 (0.0 b) TX bytes:0
(0.0 b)
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:65536 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)
[root@10-10-63-106 ~]# ip link set B netns
638
[root@10-10-63-106 ~]# ip netns exec 638 ip addr add 10.1.1.2/32 dev
B
[root@10-10-63-106 ~]# ip netns exec 638 ip
link set B up
[root@10-10-63-106 ~]# ip netns exec 638 ip
route add 10.1.1.1/32 dev B
[root@4685a85d0e11 /]# ifconfig
B
Link encap:Ethernet HWaddr
FE:38:13:D9:2F:87
inet addr:10.1.1.2
Bcast:0.0.0.0
Mask:255.255.255.255
inet6 addr: fe80::fc38:13ff:fed9:2f87/64 Scope:Link
UP BROADCAST RUNNING MULTICAST
MTU:1500 Metric:1
RX packets:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:648 (648.0 b) TX
bytes:648 (648.0 b)
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:65536 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)
在其中一台Container中ping另一台的IP地址，保证两台Container可以通信。
[root@4685a85d0e11
/]# ping 10.1.1.1
PING 10.1.1.1 (10.1.1.1) 56(84) bytes of
data.
64 bytes from 10.1.1.1: icmp_seq=1 ttl=64
time=0.084 ms
64 bytes from 10.1.1.1: icmp_seq=2 ttl=64
time=0.071 ms
64 bytes from 10.1.1.1: icmp_seq=3 ttl=64
time=0.073 ms
64 bytes from 10.1.1.1: icmp_seq=4 ttl=64
time=0.069 ms
^C
--- 10.1.1.1 ping statistics ---
4 packets transmitted, 4 received, 0%
packet loss, time 3505ms
rtt min/avg/max/mdev =
0.069/0.074/0.084/0.008 ms
参考文献：
root@10-10-63-106 ~]# docker run -i -t --rm
--net=none centos6.3-base-v2 /bin/bash
