We have an odd problem on our network where our mac-address tables on our endpoint switches are filling up very quickly. At first I thought it could be mac-flooding, and started to investigate which part of the network this could be coming from, however when looking at the mac-address-table count for each vlan I'm seeing quite an even spread of macs in each vlan, no obvious spiked anywhere. Another curious thing is that vlans that have only ever had 3 devices (2 servers, and the vlan interface) in are showing a much higher mac-address count than they should.
Is it possible that this is something is looping somewhere?
This is an example snippet from one of the endpoint 2960 switches. We have a mixture of 2950 and 2960s, and a 6509 core switch.
2960switch#sh mac-address-table count
Mac Entries for Vlan 1:
---------------------------
Dynamic Address Count : 271
Static Address Count : 0
Total Mac Addresses : 271
Mac Entries for Vlan 700:
---------------------------
Dynamic Address Count : 262
Static Address Count : 0
Total Mac Addresses : 262
Mac Entries for Vlan 703:
---------------------------
Dynamic Address Count : 264
Static Address Count : 0
Total Mac Addresses : 264
Mac Entries for Vlan 704:
---------------------------
Dynamic Address Count : 265
Static Address Count : 0
Total Mac Addresses : 265
Mac Entries for Vlan 705:
---------------------------
Dynamic Address Count : 260
Static Address Count : 0
Total Mac Addresses : 260
This continues across all the vlans, of which there are 50. Vlan705 for example is one where there have never been more than 3 mac addresses on that segment.
I can provide configs from the core.
