Event Viewer -> System log will show you when the request was accepted/denied. Otherwise, try going to IAS -> Remote Access Logging, double-click Local File, check all the boxes, try to authenticate, then head over to the directory to see what's logged.
I think the easiest way is to just run 'debug radius' on the router/switch and try it out. I just so happened to be working on a RADIUS issue this morning and have been using the debug command. Here's what I see:
Quote:
Aug 6 12:12:37.985 UTC: RADIUS/ENCODE(00001313): ask "Password: " <---This is saying that the switch has asked me for my password and is waiting for my input
Switch#
Aug 6 12:12:41.126 UTC: RADIUS/ENCODE(00001313):Orig. component type = EXEC <---I put in my password and hit Enter and the switch shows me this log
Aug 6 12:12:41.147 UTC: RADIUS(00001313): Received from id 1645/48 <---Several logs show up telling me the NAS port, port ID, etc, but this is the last one that shows up, at which point I'm sitting in Enable mode
These logs give me a good idea of how long it took the request to be accepted by the switch, sent to the RADIUS server, and for the RADIUS server to respond back granting or denying me access.
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