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Learning MAC address

I have a problem concerning a 3550-24 switch learning MAC addresses. I'm on the process of performing failover tests for a client and encountered this problem.

Below is the topology:

PIX(active) ---> 3550-24-A ---> 2621-A router

PIX(standby) ---> 3550-24-B --->2621-B router

3550-24-A ---> 3550-24-B (via cross cable)

when 3550-24-A is powered off (to simulate a defective unit), standby PIX becomes active. when 3550-24-A is powered on, a laptop connected to 3550-24-A cannot ping PIX (standby) and 2621-B but when transferred to 3550-B, can ping PIX (standby) and 2621-A but cannot ping PIX (active) and 2621-B. I found out that on 3550-A, the port connecting to 3550-B cannot learn mac-addresses from 3550-B but 3550-B port can learn mac-addresses from 3550-A. Is there a way to force a port on 3550-A to learn mac-addresses?

thanks in advance.



  • Other Network Infrastructure Subjects

Re: Learning MAC address

Well, cross check your topology for any kind of loop. Some paths could be disabled because of loops. Are the two 2621 router or the PIX connected in any way. Normally, a cisco switch will learn mac addresses. Also cross check that some mac addresses have not been assigned to any port or some other configurations on the switch.