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Catalyst 2928 Switch Software Configuration Guide
OL-23389-01
Chapter 8 Configuring Switch-Based Authentication
Controlling Switch Access with
To remove the specified server name or address, use the
no tacacs-server host
hostname
global configuration command. To remove a server group from the configuration list, use the
no aaa
group server
group-name
global configuration command. To remove the IP address of a
server, use the
no server ip-address
server group subconfiguration command.
Configuring 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 they are performed; it must be applied to a specific port before any of the defined authentication
methods are performed. The only exception is the default method list (which, by coincidence, is named
default
). The default method list is automatically applied to all ports except those that have a named
method list explicitly defined. A defined method list overrides the default method list.
A method list describes the sequence and authentication methods to be queried to authenticate a user.
You can designate one or more security protocols to be used for authentication, thus ensuring a backup
system for authentication in case the initial method fails. The software uses the first method listed to
authenticate users; if that method fails to respond, the software selects the next authentication method in
the method list. This process continues until there is successful communication with a listed
authentication method or until all defined methods are exhausted. If authentication fails at any point in
this cycle—meaning that the security server or local username database responds by denying the user
access—the authentication process stops, and no other authentication methods are attempted.
Beginning in privileged EXEC mode, follow these steps to configure login authentication:
Step 4
aaa group server
group-name
(Optional) Define the AAA server-group with a group name.
This command puts the switch in a server group subconfiguration mode.
Step 5
server
ip-address
(Optional) Associate a particular server with the defined server
group. Repeat this step for each server in the AAA server
group.
Each server in the group must be previously defined in Step 2.
Step 6
end
Return to privileged EXEC mode.
Step 7
show tacacs
Verify your entries.
Step 8
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
aaa new-model
Enable AAA.
