Concept Guide

AAA Authentication
Dell EMC Networking OS supports a distributed client/server system implemented through authentication, authorization, and accounting
(AAA) to help secure networks against unauthorized access.
In the Dell EMC Networking implementation, the Dell EMC Networking system acts as a RADIUS or TACACS+ client and sends
authentication requests to a central remote authentication dial-in service (RADIUS) or Terminal access controller access control system
plus (TACACS+) server that contains all user authentication and network service access information.
Dell EMC Networking uses local usernames/passwords (stored on the Dell EMC Networking system) or AAA for login authentication. With
AAA, you can specify the security protocol or mechanism for dierent login methods and dierent users. In Dell EMC Networking OS, AAA
uses a list of authentication methods, called method lists, to dene the types of authentication and the sequence in which they are applied.
You can dene a method list or use the default method list. User-dened method lists take precedence over the default method list.
NOTE: If a console user logs in with RADIUS authentication, the privilege level is applied from the RADIUS server if the privilege
level is congured for that user in RADIUS, whether you congure RADIUS authorization.
NOTE: RADIUS and TACACS servers support VRF-awareness functionality. You can create RADIUS and TACACS groups and
then map multiple servers to a group. The group to which you map multiple servers is bound to a single VRF.
Conguration Task List for AAA Authentication
The following sections provide the conguration tasks.
• Conguring AAA Authentication Login Methods
• Enabling AAA Authentication
• Enabling AAA Authentication - RADIUS
For a complete list of all commands related to login authentication, refer to the Security chapter in the Dell EMC Networking OS Command
Reference Guide.
Congure Login Authentication for Terminal Lines
You can assign up to ve authentication methods to a method list. Dell EMC Networking OS evaluates the methods in the order in which
you enter them in each list.
If the rst method list does not respond or returns an error, Dell EMC Networking OS applies the next method list until the user either
passes or fails the authentication. If the user fails a method list, Dell EMC Networking OS does not apply the next method list.
Conguring AAA Authentication Login Methods
To congure an authentication method and method list, use the following commands.
Dell EMC Networking OS Behavior: If you use a method list on the console port in which RADIUS or TACACS is the last authentication
method, and the server is not reachable, Dell EMC Networking OS allows access even though the username and password credentials
cannot be veried. Only the console port behaves this way, and does so to ensure that users are not locked out of the system if network-
wide issue prevents access to these servers.
1 Dene an authentication method-list (method-list-name) or specify the default.
CONFIGURATION mode
aaa authentication login {method-list-name | default} method1 [... method4]
The default method-list is applied to all terminal lines.
Possible methods are:
856
Security