I have got this scenario, Backup Domain Controller resides within my LAN, cisco secure ACS (uses RADUIS protocol) resides within my LAN as well.
ACS configuration
----------------- As you can see (Top figure) that VPN server-192.168.5.254- (concentrator 3000) was configured to be authenticated by ACS
-192.168.5.50-.
VPN 3000 Configuration
---------------------- In the bottom figure VPN server was pointed to "Server Type" as: RADUIS , and "server authentication" is : 192.168.2.11 (Backup Domain Controller ) *?* Why has it not been pointed to Cisco Secure ACS
192.168.5.50 *?*
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