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Duplicate MAC address

Hi ,

 

We have issue on 2960 switch where we are seeing duplicate MAC address on switch .

 

4c00.829d.88bf is mac address of Distribution switch and it has two vlan 1101 and 2101 which are in trunk passed to access switch of 2960 series.

 

But in the mac address table we are seeing MAC address 4c00.829d.88bf for vlan 2101 from distribution switch and 4c00.829d.88bf for vlan 1101 from different system (Attendance Clock ) connected to one of the user port. And Mac address of that system (Attendance Clock)  is 0000.c0b0.bfc1  

My Question is if the mac address 4c00.829d.88bf is of distribution switch then why access switch not learning this mac address in vlan 1101 from distribution switch and it is learning from other host which has different mac address.

 

 

Switch#sh mac address-table address 4c00.829d.88bf

          Mac Address Table

-------------------------------------------

 

Vlan    Mac Address       Type        Ports

----    -----------       --------    -----

 1101    4c00.829d.88bf    STATIC      Gi1/0/4

2101   4c00.829d.88bf    DYNAMIC     Gi2/0/49

Total Mac Addresses for this criterion: 3

 

Switch#sh mac address-table int Gi1/0/4

          Mac Address Table

-------------------------------------------

 

Vlan    Mac Address       Type        Ports

----    -----------       --------    -----

1101    0000.c0b0.bfc1    STATIC      Gi1/0/4

1101   4c00.829d.88bf    STATIC      Gi1/0/4

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