What does it mean when a MAC address is invalid?
This means a packet was received with an all zero (00:00:00:00:00:00) or a multicast source address, for example, FF:FF:FF:FF:FF:FF. which is a Layer 2 broadcast. The packet is treated as invalid and no learning is done.
Is the source port of the MAC address flooding?
We are experiencing a similar issue however, in our circumstance, the source port of the mac-address flooding is usually identifiable. When the source port is shutdown, the network stabilizes. The issue has occurred mostly on 4500 switches (4506 & 4510). The issue has impacted OSPF adjacency & Aruba wireless controllers (VLAN stability).
How to shut down ports with invalid MAC address?
Alternatively, you can also issue the switchport port-security limit rate invalid-source-mac command in order to enable port security on that interface in order to shutdown the port if the incoming rate of packets with invalid source mac address is too high. Please rate if it helps. 11-21-2012 10:29 AM
Why do I keep getting invalid packets on my switch?
Subsequent messages display the cumulative count of all such packets received in given interval on all interfaces. Check the switch configuration file in order to find the source of these packets on the specified port and take corrective action in order to fix them at the source end. For example, it can be due to a faulty NIC or connected hub.
Can a switch report an invalid MAC address?
Yes, when the switch (mainly 4500 because other platforms don´t even have the log to report such condition) receives frames with one of the following MAC addreses as “source” It reports the condition and drops the frame, nothing to be worried about.
Why are frames receiving an invalid source MAC address?
Not all access switches are directly connected to the 4500 – there is some daisy chaining of switches which was apparently done as a result of inadequate cabling. Recently i’ve noticed serror messages on the 4500 which indicate frames have been received with an invalid source mac address: