Inter switch connection without trunking

[rajesharihant]

Hello Experts, 

We have multiple 2960 switches connected to a backbone switch in star topology. 

Ofcourse, i got the Trunk interface - but is there a separate way where I dont need to specify multiple trunk ports on backbone switch for each individual 2960 switch. 

I want to exchange data among the switches. 

For many it may be pretty simple question, but I would appreciate if someone can just spare some valuable time to shade some light on this. 

Regards,

[Martin L]

yes, if they have VRF management interface you can connect them "internally"; look for vrf port next to Console port; also in running config.

most newer models do have VRF nowadays but  not all switches do;  c2960-X should have it but older 2960 models probably not;  c2960 Config docs should have instructions on how to use VRF interface

[balaji.bandi]

That is standard setup on enterprise LAN - until we miss your goal or implementation plan different which you thinking.

Core --distribution--access (this is standard way of LAN)

I want to exchange data among the switches.   - Not sure about this statement, can you explain more about the data we discussing here? VLAN information?

[Joseph W. Doherty]

". . . but is there a separate way where I dont need to specify multiple trunk ports on backbone switch for each individual 2960 switch."

Yes, two other ways come to mind.  First, if the edge switch only supports one VLAN, you don't need a trunk.  Second, using DTP might save you a little bit of configuration effort for creating your trunks.

[Giuseppe Larosa]

Hello @rajesharihant ,

you could have L2 trunk links brought up by DTP protocol as noted by @Joseph W. Doherty .

But as noted by @balaji.bandi your scenario is quite standard and L2 connectivity end to end on each VLAN require trunks either manually configured or negotiated by DTP.

To be noted that the configuration change is minimal

switchport mode trunk     ! manual configuration needed in both sides

switchport mode dynamic desirable     !  DTP active role at least one side need it to from a trunk on backbone switch ports

see more details in the following page

https://www.ciscopress.com/articles/article.asp?p=2181837&seqNum=8

The advantages of manual configuration is tha trunk port becomes trunk as soon as it is up.

And you can decide on a per link basis which VLANS are permitted

By default all are permitted but you can use

switchport trunk allowed Vlan 10,20,30-50

both sides must agree on the list of permitted Vlans and on the native Vlan number to avoid issues.

Hope to help

Giuseppe