Dead Proxy Detection?

[Lemaster, Rob]

Can FreeRADIUS detect and remove dead proxies from the round-robin rotation and then add them back after it detects that the proxy is alive again? 
 
Can FreeRADIUS automatically set all subcribers to "authenticate all" if all proxies are unavailable, and then authenticate normally automatically after the proxies come back online?
 
If these settings are available, can you reply with a link for more information?
 
Thanks!