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How to captuer filter the spanning-tree protocol in trunk interdace

I'm able to capture filter with EtheReal STP bridge MAC@01:80:c2:00:00:00 in the access interface but cannot in the switch trunk. Any idea why and how to?

Thanks in advance,

  • LAN Switching and Routing

Re: How to captuer filter the spanning-tree protocol in trunk in

Here is a link for SPAN configs on 3550 :

There are certain limitations which are mentioned in the link above :

You configure SPAN sessions by using parameters that specify the source of network traffic

to monitor. Traffic monitoring in a SPAN session has these restrictions:

You can monitor incoming traffic on a series or range of ports and VLANs.

You can monitor outgoing traffic on a single port; you cannot monitor outgoing traffic on multiple ports.

You cannot monitor outgoing traffic on VLANs.

The command syntax would be like

Switch(config)#monitor session 1 source interface fastethernet 0/2 both

Switch(config)#monitor session 1 destination interface fastethernet 0/8