Hide Navigation Pane
Show Navigation Pane
Feedback
Download
SHA1
Virtual Terminal Access Lists
You can provide additional security for your router by using access lists to restrict access to vty lines.
When the router attempts to authenticate a user, it always selects the first vty line that has an access class that permits that user’s host. The vty line’s configuration must authenticate the user to allow access. Otherwise, the user can never gain access. Consequently, we recommend that you use identical authentication configurations for all vtys that have the same access class list.
To set up access lists:
- Associate the access list with inbound Telnet sessions.host1(config)#line vty 12 15 host1(config-line)#access-class Management in
- Configure an access list.host1(config)#access-list Management permit ip 192.168.11.16 0.0.0.15 anyhost1(config)#access-list Management permit ip 192.168.4.0 0.0.0.255host1(config)#access-list Management deny ip any any
access-class in
- Use to associate the access list with vty lines.
- Example—This example sets the virtual terminal lines
to which you want to restrict access and specifies an access class
to grant access to incoming requests.host1(config)#line vty 12 15host1(config-line)#access-class Management in
- Use the no version to remove access restrictions.
- See access-class in.
access-list
- Use to configure an access list.
- Examplehost1(config)#access-list Management permit ip 192.168.11.16 0.0.0.15 any
- Use the no version to remove the access list.
- See access-list.
