Administrator Guide

login authentication {method-list-name | default}
Example of a Failed Authentication
To view the configuration, use the show config in LINE mode or the show running-config tacacs+
command in EXEC Privilege mode.
If authentication fails using the primary method, Dell Networking OS employs the second method (or third
method, if necessary) automatically. For example, if the TACACS+ server is reachable, but the server key is
invalid, Dell Networking OS proceeds to the next authentication method. In the following example, the
TACACS+ is incorrect, but the user is still authenticated by the secondary method.
First bold line: Server key purposely changed to incorrect value.
Second bold line: User authenticated using the secondary method.
Dell(conf)#
Dell(conf)#do show run aaa
!
aaa authentication enable default tacacs+ enable
aaa authentication enable LOCAL enable tacacs+
aaa authentication login default tacacs+ local
aaa authentication login LOCAL local tacacs+
aaa authorization exec default tacacs+ none
aaa authorization commands 1 default tacacs+ none
aaa authorization commands 15 default tacacs+ none
aaa accounting exec default start-stop tacacs+
aaa accounting commands 1 default start-stop tacacs+
aaa accounting commands 15 default start-stop tacacs+
Dell(conf)#
Dell(conf)#do show run tacacs+
!
tacacs-server key 7 d05206c308f4d35b
tacacs-server host 10.10.10.10 timeout 1
Monitoring TACACS+
To view information on TACACS+ transactions, use the following command.
• View TACACS+ transactions to troubleshoot problems.
EXEC Privilege mode
debug tacacs+
TACACS+ Remote Authentication
The system takes the access class from the TACACS+ server. Access class is the class of service that restricts
Telnet access and packet sizes.
If you have configured remote authorization, the system ignores the access class you have configured for the
VTY line and gets this access class information from the TACACS+ server. The system must know the
username and password of the incoming user before it can fetch the access class from the server. A user,
therefore, at least sees the login prompt. If the access class denies the connection, the system closes the
Telnet session immediately. The following example demonstrates how to configure the access-class from a
TACACS+ server. This configuration ignores the configured access-class on the VTY line. If you have
Security 802