Users Guide

Table 94. VTY Access (continued)
Authentication Method VTY access-class support? Username access-class
support?
Remote authorization
support?
TACACS+ YES NO YES (with version 5.2.1.0 and
later)
RADIUS YES NO YES (with version 6.1.1.0 and
later)
provides several ways to configure access classes for VTY lines, including:
● VTY Line Local Authentication and Authorization
● VTY Line Remote Authentication and Authorization
VTY Line Local Authentication and Authorization
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.
can assign different access classes to different users by username. Until users attempt to log in, 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, retrieves the access class from the local database and applies
it. ( 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.
Example of Configuring VTY Authorization Based on Access Class Retrieved from a Local Database (Per User)
DellEMC(conf)#user gooduser password abc privilege 10 access-class permitall
DellEMC(conf)#user baduser password abc privilege 10 access-class denyall
DellEMC(conf)#
DellEMC(conf)#aaa authentication login localmethod local
DellEMC(conf)#
DellEMC(conf)#line vty 0 9
DellEMC(config-line-vty)#login authentication localmethod
DellEMC(config-line-vty)#end
VTY Line Remote Authentication and Authorization
retrieves the access class from the VTY line.
The takes the access class from the VTY line and applies it to ALL users. 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, immediately applies it. If the access-class is set to deny all or deny for the incoming
subnet, 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.
Security
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