At the command line, type
neat which brings up a neat GUI tool for configuring the network devices.
Under the Devices tab, highlight the nic you are interested in which is eth0 this time.
Select Edit ....
[X] Activate device when computer starts
Save changes
You can also edit /etc/sysconfig/network-scripts/ifcfg-eth0
Code:
onboot is supposed to be all caps
ONBOOT=yes