Linux配置多网卡IP并保持数据出入一致

(1)创建路由表
vi /etc/iproute2/rt_tables

#定义3个路由表
252 tel
251 cnc
250 mobile

（2）为创建的路由表添加路由条目
#命令静态为3个路由表各添加1条路由条目
ip route flush table tel
ip route add default via 45.126.112.33 dev em1 src 45.126.112.37 table tel
ip rule add from 45.126.112.37 table tel

ip route flush table cnc
ip route add default via 113.209.132.145 dev em2 src 113.209.132.148 table cnc
ip rule add from 113.209.132.148 table cnc

ip route flush table mobile
ip route add default via 183.242.65.9
 dev em3 src 183.242.65.11 table mobile
ip rule add from 183.242.65.11 table mobile

（3）添加启动项，保障开机启动网络生效

vi /etc/rc.d/rc.local

/sbin/ip route flush table tel
/sbin/ip route add default via 45.126.112.33 dev em1 src 45.126.112.37 table tel
/sbin/ip rule add from 45.126.112.37 table tel

/sbin/ip route flush table cnc
/sbin/ip route add default via 113.209.132.145 dev em2 src 113.209.132.148 table cnc
/sbin/ip rule add from 113.209.132.148 table cnc

/sbin/ip route flush table mobile
/sbin/ip route add default via 183.242.65.9
 dev em3 src 183.242.65.11 table mobile
/sbin/ip rule add from 183.242.65.11 table mobile

[root@localhost ~]# ip route
default via 183.242.65.9 dev em3 
default via 45.126.112.33 dev em1 proto static metric 100 
45.126.112.32/29 dev em1 proto kernel scope link src 45.126.112.37 metric 100 
113.209.132.144/29 dev em2 proto kernel scope link src 113.209.132.148 metric 101 
183.242.65.8/29 dev em3 proto kernel scope link src 183.242.65.11 metric 102