1、查看哪个网卡为启动状态

ip a

当前网卡标记为UP状态， 修改网卡配置文件

vim /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
BOOTPROTO=none
MASTER=bond0
SLAVE=yes

vim /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
BOOTPROTO=none
MASTER=bond0
SLAVE=yes

vim /etc/sysconfig/network-scripts/ifcfg-bond0
DEVICE=bond0
TYPE=Ethernet
ONBOOT=yes
DNS1=114.114.114.114
BOOTPROTO=static
IPADDR=192.168.21.1
NETMASK=255.255.255.0
GATEWAY=192.168.21.254
USERCTL=no
BONDING_OPTS="mode=1 miimon=50"