Dell C9000 Line Cards Networking Configuration Guide for the C9000 Series Vers - Page 937

users identify themselves, the system retrieves the access class from the local database and applies it. (The system can then 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) 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 The system 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. The system 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, the system immediately applies it. If the access-class is set to deny all or deny for the incoming subnet, the system 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) 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 The system 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. Security 937