In vCenter 6.0, patching a vcenter server appliance became a straightforward and easy task.
Go to VMware Product Patches page to look for vCenter Server patches.
Select Product and Version and then download the full patch iso.
Mount the ISO to vCenter Server Appliance via vSphere Web Client or C# Client
SSH to VCSA using your favorite ssh client and make sure you are in shell mode, otherwise, type the following command to enter shell mode:
Type the following command to initiate the patching. Use --acceptEulas to skip the long Eulas, you might want to spend time to give it a read if you are not in hurry. Then just sit back and wait for the update process to complete.
software-packages install --iso --acceptEulas
Finally, reboot your server and you may proceed to upgrade your vSphere hosts.
shutdown reboot -r "Patched"
Credit to William@VirtuallyGhetto