VLAN Trunking

Unanswered Question
Dec 9th, 2008


I am having Cisco 3560 connected with Extreme (Summit-200-48) throgh trunk port but no communication between them. What could be the issue,not able to understand any idea please help me out.



I have this problem too.
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solpandor Tue, 12/09/2008 - 07:04


can you post config? when you say no communication, what have you tried so far?

maybe thre is an encaspulation mismatch?

viyuan700 Tue, 12/09/2008 - 07:17

as mentioned by solpandor

see encapsulation on your cisco id it ISL or 8021Q.

ISL is cisco Proprietary whereas 8021Q is standard based.

Check on ur other switch also

tyagi.vineet Tue, 12/09/2008 - 21:21

at both end I am using dot1q encapsulation and trunking port is also up.

viyuan700 Tue, 12/09/2008 - 21:36

can u post ur config for both switches and if u r trying to ping what address are u using.

oszamora Tue, 12/09/2008 - 17:28

on the Cisco switch do the command

show interface trunk

verify the interface you used says "trunking" if not check if the port is up/up doing a show interfaces

Did you notice any log messages regarding the port in question or trunking?


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