Addendum

Configure local authentication globally and configure access classes on a per-user basis.
FTOS can assign different access classes to different users by username. Until users attempt to log in,
FTOS does not know if they will be assigned a VTY line. This means that incoming 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, FTOS retrieves the access class from the local database and applies it. (FTOS 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 you configure 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. No access class is configured for the VTY line. It defaults from the local
database.
NOTE: For more information, refer to Access Control Lists (ACLs).
Example of Configuring VTY Authorization Based on Access Class Retrieved from a Local Database (Per
User)
FTOS(conf)#user gooduser password abc privilege 10 access-class permitall
FTOS(conf)#user baduser password abc privilege 10 access-class denyall
FTOS(conf)#
FTOS(conf)#aaa authentication login localmethod local
FTOS(conf)#
FTOS(conf)#line vty 0 9
FTOS(config-line-vty)#login authentication localmethod
FTOS(config-line-vty)#end
VTY Line Remote Authentication and Authorization
FTOS retrieves the access class from the VTY line.
The Dell Networking operating system (FTOS) takes the access class from the VTY line and applies it to
ALL users. FTOS does not need to know the 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, FTOS immediately applies it. If the access-class is set to deny all or deny for
the incoming subnet, FTOS closes the connection without displaying the login prompt. The following
example shows how to deny incoming connections from subnet 10.0.0.0 without displaying a login
prompt. The example uses TACACS+ as the authentication mechanism.
Example of Configuring VTY Authorization Based on Access Class Retrieved from the Line (Per
Network Address)
FTOS(conf)#ip access-list standard deny10
FTOS(conf-ext-nacl)#permit 10.0.0.0/8
FTOS(conf-ext-nacl)#deny any
FTOS(conf)#
FTOS(conf)#aaa authentication login tacacsmethod tacacs+
FTOS(conf)#tacacs-server host 256.1.1.2 key Force10
FTOS(conf)#
FTOS(conf)#line vty 0 9
FTOS(config-line-vty)#login authentication tacacsmethod
FTOS(config-line-vty)#
FTOS(config-line-vty)#access-class deny10
FTOS(config-line-vty)#end
(same applies for radius and line authentication)
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