Troubleshooting: device eth0 does not seem to be present, delaying initialization & grep commond for file contain search

Troubleshooting: device eth0 does not seem to be present, delaying initialization

Problem:

device eth0 does not seem to be present, delaying initialization

Possible causes:

Caused:

    New installed or replaced NIC Card
    For virtual move hard disk to another guest OS with different NIC MAC address

For CenOS:

First you must edit the each network settings in your NIC card and removed this line or edit with your new NIC card Mac Address: HWADDR=01:23:45:67:89:AB

you can edit this by:

/etc/sysconfig/network-script/ifcfg-eth0<

Short term solution:

[root@centos6 ~]# cd /sys/class/net

[root@centos6 net]# ls -l

Will show you some symbolic link with new NIC number, what you can do was to:

[root@centos6 ~]# ip link set dev eth1 name eth0 (example that old nic was eth0 and new one was read as eth1

but problem on this solution was when you reboot all the setting will do back to the original.

Permanent Solution

[root@centos6 ~]# vi /etc/udev/rules.d/70-persistent-net.rules

You need to removed the old NIC card and replace the new nic card with the correct eth0

sample

# PCI device 0x1022:0x2000 (pcnet32) (custom name provided by external tool)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0c:29:41:f6:73", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
(you must remove this bold line above)

# PCI device 0x1022:0x2000 (pcnet32)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:0c:29:b8:40:83", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
After removing the line from above change eth1 to eth0.


 Grep commond for file contain search

grep -rn 'containneed to find' . (dot means present directory)