Users Guide

them from the VTY line with a deny-all access class. After users identify themselves, Dell Networking OS retrieves the access class from
the 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 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)
Dell(conf)#user gooduser password abc privilege 10 access-class permitall
Dell(conf)#user baduser password abc privilege 10 access-class denyall
Dell(conf)#
Dell(conf)#aaa authentication login localmethod local
Dell(conf)#
Dell(conf)#line vty 0 9
Dell(config-line-vty)#login authentication localmethod
Dell(config-line-vty)#end
VTY Line Remote Authentication and Authorization
Dell 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 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, Dell Networking OS immediately applies it. If the access-class is set to deny all or
deny for the incoming subnet, Dell Networking OS 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)
Dell(conf)#ip access-list standard deny10
Dell(conf-ext-nacl)#permit 10.0.0.0/8
Dell(conf-ext-nacl)#deny any
Dell(conf)#
Dell(conf)#aaa authentication login tacacsmethod tacacs+
Dell(conf)#tacacs-server host 256.1.1.2 key Force10
Dell(conf)#
Dell(conf)#line vty 0 9
Dell(config-line-vty)#login authentication tacacsmethod
Dell(config-line-vty)#
Dell(config-line-vty)#access-class deny10
Dell(config-line-vty)#end
(same applies for radius and line authentication)
VTY MAC-SA Filter Support
Dell Networking OS supports MAC access lists which permit or deny users based on their source MAC address.
With this approach, you can implement a security policy based on the source MAC address.
To apply a MAC ACL on a VTY line, use the same access-class command as IP ACLs.
The following example shows how to deny incoming connections from subnet 10.0.0.0 without displaying a login prompt.
Example of Conguring VTY Authorization Based on MAC ACL for the Line (Per MAC Address)
Dell(conf)#mac access-list standard sourcemac
Dell(config-std-mac)#permit 00:00:5e:00:01:01
Dell(config-std-mac)#deny any
Dell(conf)#
Dell(conf)#line vty 0 9
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Security