linux 设置固定ip和dns

1. centos
2. ubuntu

1. centos

1.1 ifconfig 查看网卡名称

# ifconfig

ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.137.128  netmask 255.255.255.0  broadcast 192.168.137.255
        inet6 fe80::91b0:54db:c4f3:d9a9  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:67:b4:aa  txqueuelen 1000  (Ethernet)
        RX packets 150  bytes 24587 (24.0 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 162  bytes 21607 (21.1 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 1000  (Local Loopback)
        RX packets 738  bytes 1245656 (1.1 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 738  bytes 1245656 (1.1 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

由上面信息可知，系统目前是使用网卡ens33访问Internet的，我们要设置的就是ens33的IP地址。

1.2 设置固定ip和dns

# vim /etc/sysconfig/network-scripts/ifcfg-ens33

TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static  #静态IP
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=ens33
UUID=1d993961-7171-4a50-a17b-089cc70f96e4
DEVICE=ens33
ONBOOT=yes  #开机启动
IPV6_PRIVACY=no
CONNECTION_METERED=no
IPADDR=172.16.31.186 #本机地址
NETMASK=255.255.0.0 #子网掩码
GATEWAY=172.16.0.1 #默认网关
DNS1=172.16.0.10
DNS2=8.8.8.8

注意，后有备注的部分，按实际要求更改。

1.3 重启网络

# service network restart

2. ubuntu

2.1 ifconfig 查看网卡名称

# ifconfig

eno1      Link encap:Ethernet  HWaddr dc:f4:01:e7:11:88  
          inet addr:172.16.36.212  Bcast:172.16.255.255  Mask:255.255.0.0
          inet6 addr: fe80::def4:1ff:fee7:1188/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:13838092 errors:0 dropped:23139 overruns:0 frame:0
          TX packets:613652 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:3479806143 (3.4 GB)  TX bytes:65456575 (65.4 MB)
          Interrupt:56 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:266991 errors:0 dropped:0 overruns:0 frame:0
          TX packets:266991 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1 
          RX bytes:971472461 (971.4 MB)  TX bytes:971472461 (971.4 MB)

由上面信息可知，系统目前是使用网卡ens33访问Internet的，我们要设置的就是eno1的IP地址。

2.2 设置固定ip和dns

# sudo vim /etc/network/interfaces

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

auto eno1 # 设置网卡自启动
iface eno1 inet static  # 设置使用固定ip
address 172.16.36.212 # 设置ip
netmask 255.255.0.0 # 设置子网掩码
gateway 172.16.0.1  # 设置网关
dns-nameserver 172.16.0.10  # 设置DNS
dns-nameserver 8.8.8.8

2.3 重启网络

# sudo /etc/init.d/networking restart