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Spanning VLANs on 3524s

I am trying to SPAN an entire VLAN to port on a 3524. I want to span all of the VLAN traffic in the domain to a port, not just local traffic. I don't see a way to do this as spanning a VLAN this way doesn't appear to be an option on 3524 ports? Is there a trick I am missing.


Re: Spanning VLANs on 3524s

In my opinion, this is technically not possible. What you are observing is an expected behaviour with SPAN. The switch can not snoop the other switches vlan traffic, by default. It can SPAN only the traffic that it can see on its backplane. Not all traffic from other switches in the same VLAN/domain will reach this switch unless the destination is part of this switch.

Still there is a solution to your problem. The solution for your problem is RSPAN (Remote SPAN). You must setup Remote span in all the other switches in the domain and then SPAN it to the port that you want.

More details at

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