Explanation command line vty

[LucaSamioloNemes]

Hello, I'm Luca.

I have a Catalyst 2960-X and I have this list of vty:

line con 0
line vty 0 1
 password 
 login
line vty 2 4
 password 
 login
line vty 5
 password 
 login
line vty 6
 password 
 login
line vty 7 15
 password 
 login

could someone explain to me the meaning of these vty? are all needed for telnet connections?

Thank you very much

Best regards,

Luca

[Richard Burts]

Luca

In Cisco IOS the vty lines are used to enable remote access to the device (most especially using telnet and SSH). In early versions of IOS there were 5 vty lines (vty 0 4) and in some later versions on some platforms the number of vty was increased (vty 0 15). Some versions of IOS allow you to create additional vty lines if you need them. So you should decide how many remote access sessions you want to support at the same time. If you do not want to enable remote access then you can disable the vty lines, but you can not delete all of the vty lines.

HTH

Rick

[luis_cordova]

Hi @LucaSamioloNemes,

Adding to what Richard indicated,
When you connect by telnet, you can not decide which VTY line you will use, because the connection will be in order of arrival.
For example, the first two connections must enter the password from lines 0 to 1, while the third connection must occupy the password from lines 2 to 4.
Therefore, if you only use telnet connections, it is better to set the same password to all lines.
Now, it is recommended to use the connections by SSH, where users authenticate locally or through an AAA server, such as tacacs +.

Regards