centos6下 Device ethX does not seem to be present ,delay initialization

现象：

解决方法：
[root@s4 rules.d]# pwd
/etc/udev/rules.d
[root@s4 rules.d]# cat 70-persistent-net.rules 
##删除 70-persistent-net.rules ，重启机器

或者删除后，重启也是提示找不到网卡！
解决方法： 查看如下的文件内容
[root@localhost rules.d]# cat 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 0x8086:0x100f (e1000)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0c:29:d6:25:91", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"


# PCI device 0x8086:0x100f (e1000)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0c:29:d6:25:9b", ATTR{type}=="1", KERNEL=="eth*", NAME="eth2"

只需要将/etc/sysconfig/network-scripts下的ifcfg-ethx 改成和 这个文件中的ethx相对应就可以了！注意看网卡的mac地址
然后执行ifup ethx 即可！