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Bogus Spanning-tree?


I have a network with cat6500's as a cores, and 3500 xl switches running 12.0.wc5a. On one 3500, I have three 1200 access points (one 1231 and two 1232s running IOS 12-3.7.JA1) to provide a wireless network to allow users to roam with their laptops or spectralink phones. vlan 910 is the management native for the switches, vlan 959 is the native AP management vlan and vlan 956 is the voice vlan.

This has been in production status for over a year.

Now a few times a day I get address flap syslog messages from the 3500 switches saying that addresses are flapping between the port that the 1231 is on and the uplink to the core of the network (the 6500's). I did the debug eth controller command and noted that only 956 and 959 are duplicating macs on the ports I am getting the rtd message on.

I never receive a a dup mac on the two ports on my three data vlans, just my voice. Every couple of days I lose connectivity to the 1232s and they have to be power cycled to recover.

Anyone have any suggestions?


Re: Bogus Spanning-tree?

-- The RTD-1-ADDR_FLAP error message indicates that a MAC address is moving consistently

between different ports. This error message is only applicable on the Catalyst 2900XL and

3500XL switches.

-- If users move from one Access Point (AP) to another and the MAC address shows up on a

different switch port, the error messages are displayed. These messages do not necessarily

mean that there is a problem. They are displayed for informational purposes only.

-- It is part of normal operation for a switch to re-learn the MAC address every time it

is seen on a different port. This action always generates this message. The

RTD-1-ADDR_FLAP system status messages should not necessarily be considered errors,

particularly on ports where there are APs attached.

-- For example, if there are APs attached to ports 3/4 and 3/5, and clients associated to

those APs are roaming back and forth between the two APs, the MAC addresses of the clients

are truly moving back and forth between those two switch ports. The status messages are

accurate, and there is no cause for alarm.