Brocade Communications Systems Brocade ICX 6650 6650 Manuel D’Utilisation

TACACS and TACACS+ security

TACACS+ is an enhancement to the TACACS security protocol. TACACS+ improves on TACACS by 
separating the functions of authentication, authorization, and accounting (AAA) and by encrypting 
all traffic between the Brocade device and the TACACS+ server. TACACS+ allows for arbitrary length 
and content authentication exchanges, which allow any authentication mechanism to be utilized 
with the Brocade device. TACACS+ is extensible to provide for site customization and future 
development features. The protocol allows the Brocade device to request very precise access 
control and allows the TACACS+ server to respond to each component of that request. 

NOTE

TACACS+ provides for authentication, authorization, and accounting, but an implementation or 
configuration is not required to employ all three. 

TACACS/TACACS+ authentication, authorization,
and accounting

When you configure a Brocade device to use a TACACS/TACACS+ server for authentication, the 
device prompts users who are trying to access the CLI for a user name and password, then verifies 
the password with the TACACS/TACACS+ server.

If you are using TACACS+, Brocade recommends that you also configure authorization, in which the 
Brocade device consults a TACACS+ server to determine which management privilege level (and 
which associated set of commands) an authenticated user is allowed to use. You can also 
optionally configure accounting, which causes the Brocade device to log information on the 
TACACS+ server when specified events occur on the device.

NOTE

 By default, a user logging into the device from Telnet or SSH would first enter the User EXEC level. 
The user can enter the enable command to get to the Privileged EXEC level. 

A user that is successfully authenticated can be automatically placed at the Privileged EXEC level 
after login. Refer to 

Configuring TACACS/TACACS+ for devices in a Brocade IronStack

Because devices operating in a Brocade IronStack topology present multiple console ports, you 
must take additional steps to secure these ports when configuring TACACS/TACACS+.

The following is a sample AAA console configuration using TACACS+.

aaa authentication login default tacacs+ enable
aaa authentication login privilege-mode
aaa authorization commands 0 default  tacacs+
aaa authorization exec default  tacacs+
aaa accounting commands 0 default start-stop  tacacs+
aaa accounting exec default start-stop  tacacs+
aaa accounting system default start-stop  tacacs+
enable aaa console
hostname Fred
ip address 10.10.6.56/255
tacacs-server host 255.253.255
tacacs-server key 1 $Gsig@U\