If you’ve started using RHEL6-ish (Scientific in my case) releases with VMWare, you may run into this problem. Clone a VM from a template, boot it up and it’s network interface won’t light up. Well, we know that’s because of the hardware address mismatch in ifcfg-eth0. VMWare assigns the new VM a new hardware address automatically. What you may not have noticed, is udev renamed eth0 to eth1 and even after you fixed the problem in ifcfg-eth0, the interface still won’t light up. In order to fix this:
1. Edit /etc/udev/rules.d/70-persistent-net.rules
2. Change the end of the line, NAME=”eth1″ to NAME=”eth0″
3. Save and exit, then reboot.
Now the network interface should be up. Some people have suggested simply removing the file /etc/udev/rules.d/70-persistent-net.rules but that did not work, udev simply re-created it with the same values.