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• 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.
Congure local authentication globally and congure access classes on a per-user basis.
can assign dierent access classes to dierent 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
congure 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 congured for the VTY line. It defaults from the local database.
Example of Conguring 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 congured 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.
Example of Conguring VTY Authorization Based on Access Class Retrieved from the Line (Per Network Address)
DellEMC(conf)#ip access-list standard deny10
DellEMC(conf-ext-nacl)#permit 10.0.0.0/8
DellEMC(conf-ext-nacl)#deny any
DellEMC(conf)#
DellEMC(conf)#aaa authentication login tacacsmethod tacacs+
DellEMC(conf)#tacacs-server host 256.1.1.2 key Force10
DellEMC(conf)#
DellEMC(conf)#line vty 0 9
DellEMC(config-line-vty)#login authentication tacacsmethod
DellEMC(config-line-vty)#
DellEMC(config-line-vty)#access-class deny10
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