VTY 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 anaccess-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 usersattempt to log in, Dell Networking OS does not know if they will be assigned a VTY line. This means thatincoming users always see a login prompt even if you have excluded them from the VTY line with a deny-all access class. After users identify themselves, Dell Networking OS retrieves the access class from thelocal database and applies it. (Dell Networking OS then can close the connection if a user is deniedaccess.)NOTE: If a VTY user logs in with RADIUS authentication, the privilege level is applied from theRADIUS server only if you configure RADIUS authentication.The following example shows how to allow or deny a Telnet connection to a user. Users see a loginprompt even if they cannot log in. No access class is configured for the VTY line. It defaults from the localdatabase.Example of Configuring VTY Authorization Based on Access Class Retrieved from a Local Database (PerUser)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. DellNetworking OS does not need to know the identity of the incoming user and can immediately apply theaccess class. If the authentication method is RADIUS, TACACS+, or line, and you have configured anaccess class for the VTY line, Dell Networking OS immediately applies it. If the access-class is set to denyall or deny for the incoming subnet, Dell Networking OS closes the connection without displaying thelogin prompt. The following example shows how to deny incoming connections from subnet 10.0.0.0without displaying a login prompt. The example uses TACACS+ as the authentication mechanism.740 Security
