原文地址：https://blog.csdn.net/qq_31820885/article/details/78017864
在linux系统中输入命令:
vi /etc/sysconfig/network-scripts/ifcfg-eth0 ,然后显示如下结果
将其中的ONBOOT=no改为yes,然后输入 :wq,敲击enter保存并退出.
最后输入命令:service network restart（重启服务命令）
重启服务器,会出现正在配置IP的提示,待自动配置成功后,
输入命令ifconfig即可.
如果你是克隆出来的CentOs ,那么你可能碰到，Device eth0 does not seem to be present错误，那么你可以按照这个地址操作
https://www.linuxidc.com/Linux/2012-12/76248.htm
在VMware里克隆出来的CentOS Linux。。
ifconfig...没有看到eth0.。然后重启网卡又报下面错误。
故障现象：
service network restart
Shutting down loopback insterface: [ OK ]
Bringing up loopback insterface: [ OK ]
Bringing up interface eth0: Device eth0 does not seem to be present,delaying initialization. [FAILED]
解决办法：
首先，打开/etc/udev/rules.d/70-persistent-net.rules内容如下面例子所示：
# vi /etc/udev/rules.d/70-persistent-net.rules
# This file was automatically generated by the /lib/udev/write_net_rules
# program, run by the persistent-net-generator.rules rules file.
#
# You can modify it, as long as you keep each rule on a single
# line, and change only the value of the NAME= key.
# PCI device 0x1022:0x2000 (pcnet32)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0c:29:8f:89:9
7", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x1022:0x2000 (pcnet32)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0c:29:50:bd:1
7", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
记录下，eth1网卡的mac地址00:0c:29:50:bd:17
接下来，打开/etc/sysconfig/network-scripts/ifcfg-eth0
# vi /etc/sysconfig/network-scripts/ifcfg-eth0
将 DEVICE="eth0" 改成 DEVICE="eth1" ,
将 HWADDR="00:0c:29:8f:89:97" 改成上面的mac地址 HWADDR="00:0c:29:50:bd:17"
最后，重启网络
# service network restart
或者
# /etc/init.d/network restart
正常了。