Linux之Centos7开机之后连不上网

• 问题：ns33mtu 1500 qdisc noop state DOWN group default qlen 1000

• 解决方法：

 root@topcheer ~]# systemctl stop NetworkManager
 [root@topcheer ~]# systemctl disable NetworkManager
 Removed symlink /etc/systemd/system/multi-user.target.wants/NetworkManager.service.
 Removed symlink /etc/systemd/system/dbus-org.freedesktop.NetworkManager.service.
 Removed symlink /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service.
 Removed symlink /etc/systemd/system/network-online.target.wants/NetworkManager-wait-online.service.
 [root@topcheer ~]# service network restart
 Restarting network (via systemctl):                        [  确定  ]
 [root@topcheer ~]# ifconfig
 docker0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
         inet 172.17.0.1  netmask 255.255.0.0  broadcast 0.0.0.0
         ether 02:42:3b:db:cd:21  txqueuelen 0  (Ethernet)
         RX packets 0  bytes 0 (0.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 0  bytes 0 (0.0 B)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
 ​
 ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
         inet 192.168.180.113  netmask 255.255.255.0  broadcast 192.168.180.255
         inet6 fe80::20c:29ff:fe4d:6737  prefixlen 64  scopeid 0x20<link>
         ether 00:0c:29:4d:67:37  txqueuelen 1000  (Ethernet)
         RX packets 10  bytes 1168 (1.1 KiB)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 28  bytes 4696 (4.5 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 68  bytes 5604 (5.4 KiB)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 68  bytes 5604 (5.4 KiB)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
 ​
 virbr0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
         inet 192.168.122.1  netmask 255.255.255.0  broadcast 192.168.122.255
         ether 52:54:00:27:04:0d  txqueuelen 1000  (Ethernet)
         RX packets 0  bytes 0 (0.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 0  bytes 0 (0.0 B)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
 ​
 [root@topcheer ~]# 

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