平台信息： ubuntu 18.04 

ifconfig效果：

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 280  bytes 20667 (20.6 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 280  bytes 20667 (20.6 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

 1、查看具体信息

lshw -C network

WARNING: you should run this program as super-user.
  *-network:0 DISABLED      
       description: Ethernet interface
       product: 82545EM Gigabit Ethernet Controller (Copper)
       vendor: Intel Corporation
       physical id: 1
       bus info: pci@0000:02:01.0
       logical name: eth0
       version: 01
       serial: 00:0c:29:92:d1:71
       size: 1Gbit/s
       capacity: 1Gbit/s
       width: 64 bits
       clock: 66MHz
       capabilities: bus_master cap_list rom ethernet physical logical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=e1000 driverversion=7.3.21-k8-NAPI duplex=full latency=0 link=no mingnt=255 multicast=yes port=twisted pair speed=1Gbit/s
       resources: irq:19 memory:fd5c0000-fd5dffff memory:fdff0000-fdffffff ioport:2000(size=64) memory:fd500000-fd50ffff
  *-network:1 DISABLED
       description: Ethernet interface
       product: 82545EM Gigabit Ethernet Controller (Copper)
       vendor: Intel Corporation
       physical id: 6
       bus info: pci@0000:02:06.0
       logical name: eth1
       version: 01
       serial: 00:0c:29:92:d1:7b
       size: 1Gbit/s
       capacity: 1Gbit/s
       width: 64 bits
       clock: 66MHz
       capabilities: bus_master cap_list rom ethernet physical logical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=e1000 driverversion=7.3.21-k8-NAPI duplex=full latency=0 link=no mingnt=255 multicast=yes port=twisted pair speed=1Gbit/s
       resources: irq:16 memory:fd580000-fd59ffff memory:fdfe0000-fdfeffff ioport:2080(size=64) memory:fd520000-fd52ffff
WARNING: output may be incomplete or inaccurate, you should run this program as super-user.

注意：*-network:0 DISABLED 

2、解决方法

sudo service network-manager stop


sudo rm /var/lib/NetworkManager/NetworkManager.state


sudo service network-manager start