radtest command to test radius server

The Linux radtest is useful to test a RADIUS server without a supplicant. It usually comes with the freeradius-client package. Here is an example:

radtest ubuntu ubuntu 10.65.90.51 1812 CISCO

Here's what this command does:

  • ubuntu: The username you want to test.
  • ubuntu: The password.
  • 10.65.90.51: IP address of the RADIUS server.
  • 1812 RADIUS port number.
  • CISCO: The shared secret.

You will see a result such as:

Sent Access-Request Id 211 from 0.0.0.0:39759 to 10.65.90.51:1812 length 76
        User-Name = "ubuntu"
        User-Password = "ubuntu"
        NAS-IP-Address = 172.18.0.2
        NAS-Port = 1812
        Message-Authenticator = 0x00
        Cleartext-Password = "ubuntu"

You can also test the RADIUS server from a Cisco authentication server. Here is an example: Cisco IOS test aaa command