模拟docker桥接网络

本篇文章模拟docker桥接网络的搭建,以加深对其网络模型的理解.涉及到的知识:iptables,linux bridge,veth pair,linux namespace,unshare,nsenter等.

一.搭建图

二.创建网桥

1.安装brctl命令

yum install bridge-utils -y
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2.创建网桥并设置ip

#创建网桥 命名为br01
brctl addif br01
#网桥设置ip网段
ip addr add 172.20.0.1/16 dev br0
#启动网桥
ip link set br0 up
#使用ifconfig命令验证如下
[root@localhost ~]# ifconfig
br0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.20.0.1  netmask 255.255.0.0  broadcast 0.0.0.0
        inet6 fe80::a4c9:9fff:fe86:ab97  prefixlen 64  scopeid 0x20<link>
        ether a6:c9:9f:86:ab:97  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 14  bytes 1172 (1.1 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.100.101  netmask 255.255.255.0  broadcast 192.168.100.255
        inet6 fe80::ba99:d1d7:2105:baf7  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::ef4c:a887:b784:7528  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:b6:88:5e  txqueuelen 1000  (Ethernet)
        RX packets 4189  bytes 348799 (340.6 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 3067  bytes 367986 (359.3 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 40  bytes 3520 (3.4 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets
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