Consolidated Platform Configuration Guide, Cisco Ios Release 15.2(4)E (Catalyst 2960-X Switches - Cisco Catalyst 2960 series Configuration Manual

Command or Action
Step 2
radius-server key string
Example:
Switch(config)# radius-server key
your_server_key
Step 3 radius-server retransmit retries
Example:
Switch(config)# radius-server retransmit
5
Step 4 radius-server timeout seconds
Example:
Switch(config)# radius-server timeout
3
Step 5 radius-server deadtime minutes
Example:
Switch(config)# radius-server deadtime
0
Step 6 end
Example:
Switch(config)# end
Step 7
show running-config
Example:
Switch# show running-config
Step 8
copy running-config startup-config
Example:
Switch# copy running-config
startup-config
Purpose
Specifies the shared secret text string used between the switch and
all RADIUS servers.
Note
Specifies the number of times the switch sends each RADIUS request
to the server before giving up. The default is 3; the range 1 to 1000.
Specifies the number of seconds a switch waits for a reply to a
RADIUS request before resending the request. The default is 5
seconds; the range is 1 to 1000.
When a RADIUS server is not responding to authentication requests,
this command specifies a time to stop the request on that server. This
avoids the wait for the request to timeout before trying the next
configured server. The default is 0; the range is 1 to 1440 minutes.
Returns to privileged EXEC mode.
Verifies your entries.
(Optional) Saves your entries in the configuration file.

Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)

The key is a text string that must match the encryption key
used on the RADIUS server. Leading spaces are ignored,
but spaces within and at the end of the key are used. If you
use spaces in your key, do not enclose the key in quotation
marks unless the quotation marks are part of the key.
How to Configure RADIUS
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