原文地址：https://blog.csdn.net/qq_31820885/article/details/78017864
在linux系統中輸入命令:
vi /etc/sysconfig/network-scripts/ifcfg-eth0 ,然後顯示如下結果
將其中的ONBOOT=no改爲yes,然後輸入 :wq,敲擊enter保存並退出.
最後輸入命令:service network restart（重啓服務命令）
重啓服務器,會出現正在配置IP的提示,待自動配置成功後,
輸入命令ifconfig即可.
如果你是克隆出來的CentOs ,那麼你可能碰到，Device eth0 does not seem to be present錯誤，那麼你可以按照這個地址操作
https://www.linuxidc.com/Linux/2012-12/76248.htm
在VMware裏克隆出來的CentOS Linux。。
ifconfig...沒有看到eth0.。然後重啓網卡又報下面錯誤。
故障現象：
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]
解決辦法：
首先，打開/etc/udev/rules.d/70-persistent-net.rules內容如下面例子所示：
# 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"
記錄下，eth1網卡的mac地址00:0c:29:50:bd:17
接下來，打開/etc/sysconfig/network-scripts/ifcfg-eth0
# vi /etc/sysconfig/network-scripts/ifcfg-eth0
將 DEVICE="eth0" 改成 DEVICE="eth1" ,
將 HWADDR="00:0c:29:8f:89:97" 改成上面的mac地址 HWADDR="00:0c:29:50:bd:17"
最後，重啓網絡
# service network restart
或者
# /etc/init.d/network restart
正常了。