Default RADIUS Configuration
RADIUS and AAA are disabled by default.
To prevent a lapse in security, you cannot configure RADIUS through a network management application.
When enabled, RADIUS can authenticate users accessing the switch through the CLI.
RADIUS Server Host
Switch-to-RADIUS-server communication involves several components:
•
Hostname or IP address
•
Authentication destination port
•
Accounting destination port
•
Key string
•
Timeout period
•
Retransmission value
You identify RADIUS security servers by their hostname or IP address, hostname and specific UDP port
numbers, or their IP address and specific UDP port numbers. The combination of the IP address and the UDP
port number creates a unique identifier, allowing different ports to be individually defined as RADIUS hosts
providing a specific AAA service. This unique identifier enables RADIUS requests to be sent to multiple
UDP ports on a server at the same IP address.
If two different host entries on the same RADIUS server are configured for the same service
—
for example,
accounting
—
the second host entry configured acts as a fail-over backup to the first one. Using this example,
if the first host entry fails to provide accounting services, the %RADIUS-4-RADIUS_DEAD message appears,
and then the switch tries the second host entry configured on the same device for accounting services. (The
RADIUS host entries are tried in the order that they are configured.)
A RADIUS server and the switch use a shared secret text string to encrypt passwords and exchange responses.
To configure RADIUS to use the AAA security commands, you must specify the host running the RADIUS
server daemon and a secret text (key) string that it shares with the switch.
The timeout, retransmission, and encryption key values can be configured globally for all RADIUS servers,
on a per-server basis, or in some combination of global and per-server settings.
Related Topics
Identifying the RADIUS Server Host, on page 65
Defining AAA Server Groups, on page 68
Configuring Settings for All RADIUS Servers, on page 73
Configuring RADIUS Login Authentication, on page 66
RADIUS Login Authentication
To configure AAA authentication, you define a named list of authentication methods and then apply that list
to various ports. The method list defines the types of authentication to be performed and the sequence in which
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Configuring RADIUS
Default RADIUS Configuration