vty at switch

[Leftz]

Hi Please see the below vty. Why it has three group for vty? WS-C3850-48T version: 03.06.06E

Thanks

line vty 0 4
exec-timeout 15 0
logging synchronous
transport input ssh
line vty 5 13
transport input ssh
line vty 14 15

[balaji.bandi · Accepted solution]

The expression VTY Lines  "0 15" means the range between 0 to 15 lines (in total 16 connections in simultaneous).

The expression "0 4" will be 5 connection in simultaneous. so on different method.

[Joseph W. Doherty · Accepted solution]

As @balaji.bandi explains, if different "groups" of VTY are configured differently, they will be so group.

However, I recall (?), way back, you only could have 5 VTY lines (0..4), but later IOS versions extended this.  I also recall, some IOSs keep VTY 0 4 in their own group even when their configuration matches the VTY lines above 4.

[Richard Burts · Accepted solution]

BB and Joseph are quite correct that when some vty are configured differently from others that they show up separately in the config. Most of the vty specify transport input ssh but vty 14 and 15 do not specify this and so are separate in the config. vty 0 4 specify this

exec-timeout 15 0
logging synchronous

but the other vty do not and so 0 4 are separate in the config.

Joseph is correct in his observation that historically the vty were 0 4 (giving 5 vty connections) and that IOS typically still lists 0 4 separate from other vty. But in this case there is also a config difference between 0 4 and other vty which is the main reason that they are separate.

[Leftz]

Thank you all! 

[Richard Burts]

You are welcome. This has been a good discussion and demonstrates the vitality of this community when multiple people address the question and each provides a slightly different perspective. Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful information. This community is an excellent place to ask questions and to learn about networking. I hope to see you continue to be active in the community.

[Leftz]

Thank you Richard. I like your comments.

[Richard Burts]

You are welcome. I am glad that you like my comments. I learned a lot in communities like this one and enjoy sharing what I have learned with others.