# No nameservers found; try putting DNS servers into your
# ifcfg files in /etc/sysconfig/network-scripts like so:
#
# DNS1=xxx.xxx.xxx.xxx
# DNS2=xxx.xxx.xxx.xxx
# DOMAIN=lab.foo.com bar.foo.com
#下面是三个DNS
DNS1=172.16.0.1
DNS2=8.8.8.8
DNS3=114.114.114.114四、ip
1、查看当前配置的所有网络设备的信息
[root@localhost ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
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: eno16777728: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:83:15:cb brd ff:ff:ff:ff:ff:ff
inet 172.16.9.9/16 brd 172.16.255.255 scope global eno16777728
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe83:15cb/64 scope link
valid_lft forever preferred_lft forever后面接上指定的网卡也可以查看指定网卡的信息,也可使用ip address show
2、添加删除地址
#添加
[root@localhost ~]# ip addr add 172.16.9.10 dev eno16777728:1
[root@localhost ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
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: eno16777728: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:83:15:cb brd ff:ff:ff:ff:ff:ff
inet 172.16.9.9/16 brd 172.16.255.255 scope global eno16777728
valid_lft forever preferred_lft forever
inet 172.16.9.10/32 scope global eno16777728
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe83:15cb/64 scope link
valid_lft forever preferred_lft forever
#删除
[root@localhost ~]# ip addr del 172.16.9.10 dev eno16777728:1
[root@localhost ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
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: eno16777728: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:83:15:cb brd ff:ff:ff:ff:ff:ff
inet 172.16.9.9/16 brd 172.16.255.255 scope global eno16777728
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe83:15cb/64 scope link
valid_lft forever preferred_lft forever 3、查看现有的路由表
[root@localhost ~]# ip route show
default via 172.16.0.1 dev eno16777728 proto static metric 100
172.16.0.0/16 dev eno16777728 proto kernel scope link src 172.16.9.9 metric 100 4、添加删除路由和网关
#添加路由
[root@localhost ~]# ip route add 172.16.200.51 via 172.16.0.1 dev eno16777728 src 172.16.9.9
[root@localhost ~]# ip route show
default via 172.16.0.1 dev eno16777728 proto static metric 100
172.16.0.0/16 dev eno16777728 proto kernel scope link src 172.16.9.9 metric 100
172.16.200.51 via 172.16.0.1 dev eno16777728 src 172.16.9.9
#172.16.200.51为目标ip
#172.16.0.1为路由
#172.16.9.9为源ip
#删除路由
[root@localhost ~]# ip route del 172.16.200.51
[root@localhost ~]# ip route
default via 172.16.0.1 dev eno16777728 proto static metric 100
172.16.0.0/16 dev eno16777728 proto kernel scope link src 172.16.9.9 metric 100
#添加默认网关
[root@localhost ~]# ip route add default via 172.16.0.1 dev eno16777728
[root@localhost ~]# ip route show
default via 172.16.0.1 dev eno16777728
default via 172.16.0.1 dev eno16777728 proto static metric 100
172.16.0.0/16 dev eno16777728 proto kernel scope link src 172.16.9.9 metric 100
#删除刚才添加的网关
[root@localhost ~]# ip route del default via 172.16.0.1 dev eno16777728
[root@localhost ~]# ip route
default via 172.16.0.1 dev eno16777728 proto static metric 100
172.16.0.0/16 dev eno16777728 proto kernel scope link src 172.16.9.9 metric 1004、关闭网卡修改网卡名称
[root@localhost ~]# ip link set eno16777728 down
[root@localhost ~]# ip link set eno16777728 name eth0
[root@localhost ~]# ip link set show
[root@localhost ~]# ip link set eth0 up
#这样就把eno16777728改为了eth0,但是因为/etc/sysconfig/network-scripts/ifcfg-eno16777728还是原来的
#名字所以,配置不会跟着到eth0上,所以要完整的改名需要改变此配置文件中NAME=eth0,并将此文件名改为
#ifcfg-eth0五、netstat
netstat命令主要用来查看整个系统的网络情况
1、前面所有的修改网络参数的命令在重启系统之后就会失效,只有更改网络配置文件/etc/sysconfig/network-scripts/ifcfg-eno16777728【注意这是Centos7的,Centos6为ifcfg-eth0】在重启之后才会有效
[root@localhost network-scripts]# vim /etc/sysconfig/network-scripts/ifcfg-eno16777728