参数
-a 显示全部接口信息
[root@controller hello]# ifconfig -a
enp0s3: flags=4419<UP,BROADCAST,RUNNING,PROMISC,MULTICAST> mtu 1500
inet 192.168.10.202 netmask 255.255.255.0 broadcast 192.168.10.255
inet6 fe80::a00:27ff:febc:4068 prefixlen 64 scopeid 0x20<link>
ether 08:00:27:bc:40:68 txqueuelen 1000 (Ethernet)
RX packets 132991 bytes 86829278 (82.8 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 73175 bytes 13137262 (12.5 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
enp0s8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.56.102 netmask 255.255.255.0 broadcast 192.168.56.255
inet6 fe80::a00:27ff:fe78:76c3 prefixlen 64 scopeid 0x20<link>
ether 08:00:27:78:76:c3 txqueuelen 1000 (Ethernet)
RX packets 15992 bytes 1550956 (1.4 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 6044 bytes 1022821 (998.8 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 1 (Local Loopback)
RX packets 15273888 bytes 1929203265 (1.7 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 15273888 bytes 1929203265 (1.7 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
-s 显示摘要信息
[root@controller hello]# ifconfig -s
Iface MTU RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
enp0s3 1500 133056 0 0 0 73204 0 0 0 BMPRU
enp0s8 1500 15995 0 0 0 6048 0 0 0 BMRU
lo 65536 15278612 0 0 0 15278612 0 0 0 LRU
启动或关闭指定网卡
ifconfig eth0 up
ifconfig eth0 down
ifup eth0
ifdown eth0
-promisc 设置是否支持网卡的promiscuous模式
如果选择此参数，网卡将接收网络中发给它所有的数据包
ifconfig eth0 promisc ／／设置
ifconfig eth0 -promisc ／／取消
-allmulti 设置是否支持多播模式
ifconfig eth0 allmulti ／／设置
ifconfig eth0 -allmulti ／／取消
如果选择此参数，网卡将接收网络中所有的多播数据包
配置IP地址
ifconfig eth0 192.168.120.56
ifconfig eth0 192.168.120.56 netmask 255.255.255.0
ifconfig eth0 192.168.120.56 netmask 255.255.255.0 broadcast 192.168.120.255
单网卡添加多个IP地址
ifconfig eth0:0 192.168.0.1 netmask 255.255.255.0 up
ifconfig eth0:1 192.168.0.2 netmask 255.255.255.0 up
删除IP地址
ifconfig eth0 del 192.168.227.188
启用或关闭arp协议
ifconfig eth0 arp
ifconfig eth0 -arp
设置最大传输单元
设置能通过的最大数据包大小为 1500 bytes
ifconfig eth0 mtu 1500
用ifconfig修改MAC地址
ifconfig eth0 hw ether 00:AA:BB:CC:DD:EE
注意：使用ifconfig配置的网络信息，在网卡重启或者机器重启之后就失效了。如需永久保留，请在配置文件中持久化保存。
