How to release and Renew DHCP address with cisco router

Whaooo, it is so easy to release and renew dhcp with cisco router.

To release :

R2_2611XM#release dhcp fa0/0


to renew :

R2_2611XM#renew dhcp fa0/0

Source:
http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gtdhcprr.html