After some further testing on this, it turns out the 2800 series switches do not support radius authentication for managing the switch. It supports radius for dynamic vlan assignment/ dot1x operations. You will need to stick with local authentication. I apologize about my initial misinformation.
Hi, I am trying to enable Radius authentication on an 2848 (to W2k12). I've tried following this guide - [URL] or this older one [URL]  Both require configuration on the switch via telnet using the aaa command. Now as it seems the 2848 does not have that particular command. I have set up the switch to my best knowledge using the GUI (according to info from manual), but its not working. Is there a guide working for the 2800 series on how to configure this on Switch/Remote side?  Thanks
Dell 2848 Radius