%SW_MATM-4-MACFLAP_NOTIF issue

[Lee Win Neng]

Hi all, 

I have one inquiries regarding on the MAC Flapping error as shown below.

Switch Model = WS-C3650-48TS

Switch Version = 03.07.01E

VLAN 99 = Server Management

Interface 1/0/38, 1/0/20 & 1/0/24 is an access port on VLAN 99 connecting to different server without any hub in between.

Interface Po1 is a trunk port as uplink connecting to core switch.

Interface Po2 is a trunk port as downlink connecting to cascade switch.

Jun 7 15:44:29.000: %SW_MATM-4-MACFLAP_NOTIF: Host 0022.19a4.f9b4 in vlan 99 is flapping between port Gi1/0/38 and port Po1
Jun 7 15:44:29.003: %SW_MATM-4-MACFLAP_NOTIF: Host 0014.c29c.4b76 in vlan 99 is flapping between port Gi1/0/38 and port Po1
Jun 7 15:44:29.004: %SW_MATM-4-MACFLAP_NOTIF: Host 0022.19bd.76f1 in vlan 99 is flapping between port Gi1/0/38 and port Gi1/0/20
Jun 7 15:44:29.004: %SW_MATM-4-MACFLAP_NOTIF: Host 0022.19bc.a477 in vlan 99 is flapping between port Gi1/0/38 and port Gi1/0/24
Jun 7 15:44:29.007: %SW_MATM-4-MACFLAP_NOTIF: Host 001e.c9f7.0658 in vlan 99 is flapping between port Gi1/0/38 and port Po1
Jun 7 15:44:29.008: %SW_MATM-4-MACFLAP_NOTIF: Host 0021.5e82.07ac in vlan 99 is flapping between port Gi1/0/38 and port Po1
Jun 7 15:44:29.010: %SW_MATM-4-MACFLAP_NOTIF: Host 001e.c9ce.4a89 in vlan 99 is flapping between port Gi1/0/38 and port Po1

But we are seeing this mac flapping error logs for 2 minutes and goes disappear, I had checked on the spanning-tree mst that configured but everything was looking fine. 

Kindly need some advice that does the switch version hitting any bugs or any similar case faced before? Thank you.

[Leo Laohoo]

Trace where these MAC address are coming from. There is a strong chance some may have installed an un-authorized & un-managed switch in your network.

[Lee Win Neng]

Hi, 

Thank you for your reply while the issue was happened around 2 minutes and network had back to normal which I had not enough time to trace down the MAC address.

While do you have any suggestion/advice that it might be causing because of physical port or cable faulty, switch firmware issue or any bugs?

[Georg Pauwen]

Hello,

on a side note, try and disable IPDT on the switch:

no ip device track

[Lee Win Neng]

Hi, 

Thanks for your advice while disable IPDT will not impacting any spanning-tree or network issue if there is a looping detected in future right?