原文地址https://www.linuxidc.com/Linux/2018-05/152427.htm
vim /etc/init.d/network的倒数第二行，也就是exit $rc上一行加上如下
10的代表内网的，168的代表外网的，via后面是网关src是网卡ip
ip route flush table 1

ip route add default via 10.0.7.254 dev eth0 src 10.0.7.2 table 1

ip rule add from 10.0.7.2 table 1

ip route flush table 2

ip route add default via 168.6.101.254 dev eth1 src 168.6.101.2 table 2

ip rule add from 168.6.101.2 table 2

注意，要先disable掉NetworkManager这个服务
systemctl disable NetworkManager
systemctl stop NetworkManager
必须只由network服务来掌管network
systemctl restart network