3Com 4210 9-Port - Troubleshooting AAA; Troubleshooting RADIUS Configuration; Troubleshooting HWTACACS Configuration

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Troubleshooting AAA
Troubleshooting RADIUS Configuration
The RADIUS protocol operates at the application layer in the TCP/IP protocol suite. This protocol
prescribes how the switch and the RADIUS server of the ISP exchange user information with each
other.
Symptom 1: User authentication/authorization always fails.
Possible reasons and solutions:
z The user name is not in the userid@isp-name or userid.isp-name format, or the default ISP domain
is not correctly specified on the switch — Use the correct user name format, or set a default ISP
domain on the switch.
z The user is not configured in the database of the RADIUS server — Check the database of the
RADIUS server, make sure that the configuration information about the user exists.
z The user input an incorrect password — Be sure to input the correct password.
z The switch and the RADIUS server have different shared keys — Compare the shared keys at the
two ends, make sure they are identical.
z The switch cannot communicate with the RADIUS server (you can determine by pinging the
RADIUS server from the switch) — Take measures to make the switch communicate with the
RADIUS server normally.
Symptom 2: RADIUS packets cannot be sent to the RADIUS server.
Possible reasons and solutions:
z The communication links (physical/link layer) between the switch and the RADIUS server is
disconnected/blocked — Take measures to make the links connected/unblocked.
z None or incorrect RADIUS server IP address is set on the switch — Be sure to set a correct
RADIUS server IP address.
z One or all AAA UDP port settings are incorrect — Be sure to set the same UDP port numbers as
those on the RADIUS server.
Symptom 3: The user passes the authentication and gets authorized, but the accounting information
cannot be transmitted to the RADIUS server.
Possible reasons and solutions:
z The accounting port number is not properly set — Be sure to set a correct port number for RADIUS
accounting.
z The switch requests that both the authentication/authorization server and the accounting server
use the same device (with the same IP address), but in fact they are not resident on the same
device — Be sure to configure the RADIUS servers on the switch according to the actual situation.
Troubleshooting HWTACACS Configuration
See the previous section if you encounter an HWTACACS fault.