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Static Multicast MAC address

Why is my switch showing a static mac entry that I do not have configured??

The MAC address is a multicast mac from a sidewinder firewall that I have statically assigned to two ports, 2/44 and 2/47.

Why is it also showing up on port 1/23 which is connected to another router?

BDN_DMZ1RT#sh mac-address-table | i af02

* 3 0100.5e1d.af02 static Yes - Gi2/44,Gi2/47

BDN_DMZ1RT#sh run | i mac

mac-address-table static 0100.5e1d.af02 vlan 3 interface GigabitEthernet2/44 GigabitEthernet2/47


Re: Static Multicast MAC address

To identify the end station that is generating frames with a multicast source MAC address. Typically, such frames are transmitted from a traffic generator (for example, Smart Bits) or third party devices that share a multicast MAC address, such as a load balancing firewall or server product.

Use a sniffer to identify the device generating the frames with multicast MAC addresses as source MAC addresses. This must be done at the time the messages are being logged.

For the further detail for the command  sh mac-address-table  refer the url :

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