Susindran,
When you discover a server with both server and IDRAC ip , it is expected that you see an entry under 'RAC' and 'Server' group.
To perform system updates through IDRAC, you must discover and inventory the IDRAC using WSMAN protocol. So you see the message under 'Issues and Resolution' tab.
In your case you can still perform system updates through the OS if OMSA is installed on the server.
Lakshmi.