This link from the Redhat knowledge base talks all about it.
Here’s the list of steps and pointers I had to go through.
1. Make sure that the 8021q module is loaded
2. This step is important as it defines the vlan that it listens on
Make a new interface file named “ifcfg-ethX.Y” where
X – the interface it will listen on.
Y – is the VLAN ID.
Add this to the config file
3. Create the neccessary IP configurations on the new interface file
4. Make sure that physical interface file looks like this. In my case it’s eth0
5. service network restart