Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Static MAC address without configuration


i am a german guy, so please excuse my bad english.

I have a question about static MAC addresses on a WS-C3750G-48TS Switch.

I have no static adresses configured on my switch, but see some when execute the "show mac address-table static" command. And i mean not the 0000.0c07.ac01 addresse for HSRP, Spanning-tree or something else, which are forwarded to the CPU, i mean entries like this:

Switch#show MAC address-table interface g2/0/47
          Mac Address Table

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
   3    1212.1212.1212    STATIC      Gi2/0/47
   3    1414.1414.1414    STATIC      Gi2/0/47
Total Mac Addresses for this criterion: 2

This entries not configured or dynamicly learned.

I suspected functions like gratitious-arp, but this is only for IP<->MAC translation. Then i have searched functions like gratitious-mac or mac-notification. I have searched for a function with tells the switchport: "Hey, that is my MAC address. There is no need to learn this address dynamicly", but with no luck.

Does anybody can tell me, why these MAC addresses are shown static, and not dynamicly?


Thanks for help.


Cisco Employee

Hi Thomas,Are there any port

Hi Thomas,

Are there any port-security related configurations in interface Gi2/0/47? Could you post the running-configuration of this interface in concern, output of show mac-address-table interface Gi2/0/47 and also could you let me know what is connected to this interface?




CreatePlease login to create content