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Error: "Unable to communicate with RADIUS Server" in AARadiusTest.exe


When attempting to use AARadiusTest.exe from an IP address that RADIUS is not listening on receive the error "Unable to communicate with RADIUS server". 



AuthAnvil RADIUS Server listens for defined IP addresses on a specific port. There are several reasons you may see this message: 

  1. No RADIUS client configured to listen on the incoming IP address
  2. No RADIUS Server running at the destination IP, or the RADIUS service is not started
  3. Port number does not match the RADIUS configuration
  4. Firewall is blocking the request from reaching the RADIUS server
  5. Microsoft NPS / RRAS has priority of the default RADIUS port, preventing incoming requests to the AuthAnvil RADIUS server



Here are some general troubleshooting steps to resolve the issues above: 

  1. Open AARadiusWizard.exe at C:\Program Files\Scorpion Software\AuthAnvil Radius Server and review the Port and the Radius Clients pages to make sure you are listening for the correct IP addresses on a proper port. Each "Radius Client" represents the IP Address of a machine that will be sending RADIUS requests to the AuthAnvil RADIUS server.
  2. Check the AuthAnvil RADIUS Server service in the services.msc Windows snap-in. Make sure it exists and that it is Started.
  3. Make sure the RADIUS port is opened through the firewall (1812 by default)
  4. If Microsoft NPS / RRAS is installed, it will have port 1812 and 1813 dedicated to its own functions. You must use 1814 or another port for AuthAnvil RADIUS Server



All versions of AuthAnvil RADIUS server



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