1. ip link
[root@WWcentos ~]# ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
link/ether 00:0c:29:56:45:4d brd ff:ff:ff:ff:ff:ff
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000
link/ether 52:54:00:7c:a8:40 brd ff:ff:ff:ff:ff:ff
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN mode DEFAULT group default qlen 1000
link/ether 52:54:00:7c:a8:40 brd ff:ff:ff:ff:ff:ff
（1）：up / down 启动 / 关闭设备。 示例：#ip link set dev ens33 up
（2）：修改网络设备的MAC地址。 示例：#ip link set dev ens33 address 00:01:4f:00:15:f1
2. ip address
（1）：ip address add 添加一个新的协议地址。给某个具体接口配置，也就是给网卡配ip。（需要有ip地址和对应的掩码）
示例：#ip address add 192.168.137.129/24 dev ens33
[root@WWcentos ~]# ip address add 192.168.137.129/24 dev ens33
[root@WWcentos ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:0c:29:56:45:4d brd ff:ff:ff:ff:ff:ff
inet 192.168.137.128/24 brd 192.168.137.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet 192.168.137.129/24 scope global secondary ens33
valid_lft forever preferred_lft forever
inet6 fe80::280a:2526:a6e5:ae9a/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether 52:54:00:7c:a8:40 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
link/ether 52:54:00:7c:a8:40 brd ff:ff:ff:ff:ff:ff
注意：重启网络后即会失效
[root@WWcentos ~]# systemctl restart network
[root@WWcentos ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:0c:29:56:45:4d brd ff:ff:ff:ff:ff:ff
inet 192.168.137.128/24 brd 192.168.137.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet6 fe80::280a:2526:a6e5:ae9a/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether 52:54:00:7c:a8:40 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
link/ether 52:54:00:7c:a8:40 brd ff:ff:ff:ff:ff:ff（2）ip address delete 删除一个协议地址
3. route 路由表管理
[root@WWcentos ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.137.2 0.0.0.0 UG 100 0 0 ens33
192.168.122.0 0.0.0.0 255.255.255.0 U 0 0 0 virbr0
192.168.137.0 0.0.0.0 255.255.255.0 U 100 0 0 ens33（1）ip route add 添加新路由
（2）ip route change 修改路由
（3）ip route replace 替换已有的路由
（4）ip route delete 删除路由
示例1：在虚拟机添加一个网卡，设置到网络192.168.65.0的路由经过网关192.168.137.2
添加前：
[root@192 ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.137.2 0.0.0.0 UG 100 0 0 ens33
192.168.137.0 0.0.0.0 255.255.255.0 U 100 0 0 ens33在虚拟机设置里新添加一个网络适配器，设置为仅主机模式：
添加后：
[root@192 ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.137.2 0.0.0.0 UG 100 0 0 ens33
192.168.65.0 0.0.0.0 255.255.255.0 U 101 0 0 ens37
192.168.137.0 0.0.0.0 255.255.255.0 U 100 0 0 ens33
[root@192 ~]# ip route add 192.168.65.0/24 via 192.168.137.2
[root@192 ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.137.2 0.0.0.0 UG 100 0 0 ens33
192.168.65.0 192.168.137.2 255.255.255.0 UG 0 0 0 ens33
192.168.65.0 0.0.0.0 255.255.255.0 U 101 0 0 ens37
192.168.137.0 0.0.0.0 255.255.255.0 U 100 0 0 ens33
[root@192 ~]# ip route
default via 192.168.137.2 dev ens33 proto dhcp metric 100
192.168.65.0/24 via 192.168.137.2 dev ens33
192.168.65.0/24 dev ens37 proto kernel scope link src 192.168.65.128 metric 101
192.168.137.0/24 dev ens33 proto kernel scope link src 192.168.137.137 metric 100示例2：删除设置到网络192.168.65.0的路由经过网关192.168.137.2
[root@192 ~]# ip route delete 192.168.65.0/24 via 192.168.137.2
[root@192 ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.137.2 0.0.0.0 UG 100 0 0 ens33
192.168.65.0 0.0.0.0 255.255.255.0 U 101 0 0 ens37
192.168.137.0 0.0.0.0 255.255.255.0 U 100 0 0 ens33
[root@192 ~]# ip route
default via 192.168.137.2 dev ens33 proto dhcp metric 100
192.168.65.0/24 dev ens37 proto kernel scope link src 192.168.65.128 metric 101
192.168.137.0/24 dev ens33 proto kernel scope link src 192.168.137.137 metric 100（4）ip route flush 擦除路由表（轻易勿动！）
示例1：删除路由表main中的所有网关路由（在路由监控程序挂掉之后）：
#ip -4 route flush scope global type unicast
示例2：清除所有ipv4路由cache
#ip route flush cache
* * * IPv4 routing cache is flushed