%SW_MATM-4-MACFLAP_NOTIF: flapping

[AfidzRIght21]

Hi,

Can someone help with VLAN flapping Issue, I have a topology like this:

Router > Cisco SG300 > Cisco C2960 > Cisco SF300-24P

a Flapping appear in sw c2960, SF300-24P actually passed c2960, but at SF300-24P not appear flapping

and get error message:

Dec  1 22:59:14.943: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b22.4cfd in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/34
Dec  1 22:59:17.725: %SW_MATM-4-MACFLAP_NOTIF: Host 902b.3478.8ca5 in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/16
Dec  1 22:59:38.284: %SW_MATM-4-MACFLAP_NOTIF: Host 902b.3478.8ca5 in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/16
Dec  1 22:59:56.484: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b22.4cfd in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/34
Dec  1 23:00:11.573: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b22.4cfd in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/34
Dec  1 23:00:11.643: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b8b.6394 in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/47
Dec  1 23:00:38.731: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b22.4cfd in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/34
Dec  1 23:00:43.771: %SW_MATM-4-MACFLAP_NOTIF: Host 902b.3478.8ca5 in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/16
Dec  1 23:00:49.105: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b22.4cfd in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/34
Dec  1 23:04:29.715: %SW_MATM-4-MACFLAP_NOTIF: Host 448a.5b22.4cfd in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/34
Dec  1 23:04:30.473: %SW_MATM-4-MACFLAP_NOTIF: Host a45d.36d1.1b1d in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/27
Dec  1 23:04:31.952: %SW_MATM-4-MACFLAP_NOTIF: Host 1458.d017.4e6b in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/25
Dec  1 23:04:51.833: %SW_MATM-4-MACFLAP_NOTIF: Host 902b.3478.8ca5 in vlan 3 is flapping between port Gi1/0/51 and port Gi1/0/16

Cisco SG300 Configuration

interface gigabitethernet27
 description TRUNK-TO-SW1-R.ELEKTRO
 no spanning-tree portfast
 switchport trunk allowed vlan add 2-3
 switchport trunk native vlan 99

Cisco C2960 Configuration

sh running-config interface Gi1/0/51
Building configuration...

Current configuration : 185 bytes
!
interface GigabitEthernet1/0/51
 description TO-SW-IT
 switchport trunk native vlan 99
 switchport trunk allowed vlan 2,3
 switchport mode trunk
 spanning-tree bpdufilter enable
end

I'm really confused why this happened, can anybody help me ?

Thanks..

[anuarus]

it came down to the APs fine-tuning.

we migrated systems from aerohive to ruckus and the problem went away, 

our aerohives were very outdated an the new ruckus handles the client handout much more graciously

hence eliminating the issue altogether.

[muhammadfadhila230]

Hello anuarus, 

may I know how your ruckus is configured, my ruckus makes flapping

did you check the load balancing section?

[nikhil kumar1]

I tried this and it worked for me. Thanks

%SW_MATM-4-MACFLAP_NOTIF or MAC Flapping Cisco Switch (edledge.com)

[Chicho]

Good day everyone,

We have had this problem of a loop that was caused by a voip phone connected on its PC port back on to the switch port. This issue affected the PCs' connection while on LAN not on WI-FI simply because the flapping is on data vlan 101 as what you can see on the output below. WI-FI is on vlan 500. 

NB: The quick and easy way to keep track of the device that is causing the loop is to show cdp nei on every switch one by one.
Nov 29 10:58:07.875: %SW_MATM-4-MACFLAP_NOTIF: Host 083a.8869.27ce in vlan 101 i s flapping between port Gi1/0/47 and port Gi1/0/44
Nov 29 10:58:07.931: %SW_MATM-4-MACFLAP_NOTIF: Host 083a.8869.8a01 in vlan 101 i s flapping between port Gi1/0/44 and port Gi1/0/47
Nov 29 10:58:08.035: %SW_MATM-4-MACFLAP_NOTIF: Host 0020.6bf4.1ef3 in vlan 101 i s flapping between port Gi1/0/44 and port Gi1/0/47
Nov 29 10:58:08.155: %SW_MATM-4-MACFLAP_NOTIF: Host 083a.8869.a506 in vlan 101 i s flapping between port Gi1/0/47 and port Gi1/0/44
Nov 29 10:58:08.187: %SW_MATM-4-MACFLAP_NOTIF: Host 6c03.0928.4ec1 in vlan 101 i s flapping between port Gi1/0/44 and port Gi1/0/47
Nov 29 10:58:08.615: %STORM_CONTROL-3-FILTERED: A Multicast storm detected on Gi 1/0/44. A packet filter action has been applied on the interface.

[chou.yang]

What was the resolution?

[nikhil kumar1]

Hi @chou.yang ,

Try this => %SW_MATM-4-MACFLAP_NOTIF or MAC Flapping Cisco Switch

It worked for me.