一.故障现象：[root@c1node01 ~]# service network restartShutting 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：[root@c1node01 ~]# rm -rf /etc/udev/rules.d/70-persistent-net.rules[root@c1node01 ~]# reboot ………………[root@c1node01 ~]# service network restartShutting down loopback insterface: [ OK ]Bringing up loopback insterface: [ OK ]Bringing up interface eth0: [ OK ][root@c1node01 ~]#二.另一种方法造成这样的原因，是因为在虚拟机（Vmware）中移动了Centos系统对应的文件，导致重新配置时，网卡的MAC地址变了，输入ifconfig -a,找不到eth0·······安装完一个centos虚拟机，又拷贝一份，开机后网卡无法正常启动，报错：Device eth0 does not seem to be present,

delaying initialization

解决：# mv /etc/sysconfig/network-scripts/ifcfg-eth0

sysconfig/network-scripts/ifcfg-eth1

vim

sysconfig/network-scripts/ifcfg-eth1

修改DEVICE="eth0"

为DEVICE="eth1"

可删掉uuid、物理地址

然后重启启动网卡尝试下三.比第一种更深入一点

故障前的操作：

DELL刀片装的是CentOS6.3的操作系统，网卡识别的是em1和em2，由于工作需要做了槽位调整，并启动了刀片

故障现象：

启动后网络不通，通过iDRAC登录后route查看缺省路由正常；

重启网络服务：

[root@nodeA ~]# service network restart Shutting down loopback insterface: [ OK ] Bringing up loopback insterface: [ OK ] Bringing up interface em1: Device em1 does not seem to be present,delaying initialization. [FAILED]

分析问题和解决：

之前在别的文章中我们提过70-persistent-net.rules文件，所以看了一下：

[root@nodeA ~]# 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 0x14e4:0x163a (bnx2) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="24:b6:fd:ab:76:1e", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"

# PCI device 0x14e4:0x163a (bnx2) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="24:b6:fd:ab:76:1c", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

发现NAME的名称不正确，依次将上述红色字体中的eth0改为em1，eth1改为em2；

*切记：网卡编号由MAC地址大小决定，MAC越小网卡编号越小；

如下：

…………

# PCI device 0x14e4:0x163a (bnx2)

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="24:b6:fd:ab:76:1e", ATTR{type}=="1", KERNEL=="eth*", NAME="em2"

# PCI device 0x14e4:0x163a (bnx2) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="24:b6:fd:ab:76:1c", ATTR{type}=="1", KERNEL=="eth*", NAME="em1"

保存退出~！

[root@nodeA ~]#reboot

………………