Authentication Method VTY access-class support? Username access-classsupport? Remote authorization support?TACACS+ YES NO YES (with Dell Networking OSversion 5.2.1.0 and later)RADIUS YES NO YES (with Dell Networking OSversion 6.1.1.0 and later)Dell Networking OS provides several ways to configure access classes for VTY lines, including:• VTY Line Local Authentication and Authorization• VTY Line Remote Authentication and AuthorizationVTY Line Local Authentication and AuthorizationDell Networking OS retrieves the access class from the local database.To use this feature:1 Create a username.2 Enter a password.3 Assign an access class.4 Enter a privilege level.You can assign line authentication on a per-VTY basis; it is a simple password authentication, using an access-class as authorization.Configure local authentication globally and configure access classes on a per-user basis.Dell Networking OS can assign different access classes to different users by username. Until users attempt to log in, Dell Networking OSdoes not know if they will be assigned a VTY line. This means that incoming users always see a login prompt even if you have excludedthem from the VTY line with a deny-all access class. After users identify themselves, Dell Networking OS retrieves the access class fromthe local database and applies it. (Dell Networking OS then can close the connection if a user is denied access.)NOTE: If a VTY user logs in with RADIUS authentication, the privilege level is applied from the RADIUS server only if youconfigure RADIUS authentication.The following example shows how to allow or deny a Telnet connection to a user. Users see a login prompt even if they cannot log in. Noaccess class is configured for the VTY line. It defaults from the local database.Example of Configuring VTY Authorization Based on Access Class Retrieved from a Local Database (Per User)Dell(conf)#user gooduser password abc privilege 10 access-class permitallDell(conf)#user baduser password abc privilege 10 access-class denyallDell(conf)#Dell(conf)#aaa authentication login localmethod localDell(conf)#Dell(conf)#line vty 0 9Dell(config-line-vty)#login authentication localmethodDell(config-line-vty)#endVTY Line Remote Authentication and AuthorizationDell Networking OS retrieves the access class from the VTY line.The Dell Networking OS takes the access class from the VTY line and applies it to ALL users. Dell Networking OS does not need to knowthe identity of the incoming user and can immediately apply the access class. If the authentication method is RADIUS, TACACS+, or line,and you have configured an access class for the VTY line, Dell Networking OS immediately applies it. If the access-class is set to deny all ordeny for the incoming subnet, Dell Networking OS closes the connection without displaying the login prompt. The following example shows780 Security
