I am working with a network containing several Catalyst 3550 switches at the core and several unmanaged switches of various manufacture outlying.
In summary, SWITCH_01 sees it flapping across 5 interfaces; Gi0/2, Fa0/1, Fa0/4, Fa0/19, and Fa0/23. Fa0/1, 19, and 23 are servers. Fa0/2 is a crossover cable to SWITCH_02. Gi0/2 is fiber connected to SWITCH_10-Gi0/2.
SWITCH_02 sees it flapping across two interfaces; Fa0/5 and Fa0/20. Fa0/5 is the crossover link to SWITCH_01. Fa0/20 is a crossover link to an unmanaged gigabit switch.
SWITCH_10 sees this mac on two interfaces; Gi0/2 and Gi0/1. Gi0/1 is connected to SWITCH_M1-Gi0/2. Gi0/2 is the fiber link back to SWITCH_01.
SWITCH_M1 sees it flapping across two interfaces; Gi0/2 and Fa0/9. Gi0/2 is the link to SWITCH_10. Fa0/9 is some device with an HP nic.
Only SWITCH_01 and SWITCH_10 are logging MACFLAP errors even though SWITCH_02 and SWITCH_M1 are clearly seeing it flap:
SWITCH_01>
%SW_MATM-4-MACFLAP_NOTIF: Host 0201.0000.0000 in vlan 1 is flapping between port Gi0/2 and port Fa0/4 %SW_MATM-4-MACFLAP_NOTIF: Host 0201.0000.0000 in vlan 1 is flapping between port Fa0/1 and port Fa0/23 %SW_MATM-4-MACFLAP_NOTIF: Host 0201.0000.0000 in vlan 1 is flapping between port Fa0/19 and port Gi0/2
SWITCH_10>
%SW_MATM-4-MACFLAP_NOTIF: Host 0201.0000.0000 in vlan 1 is flapping between port Gi0/1 and port Gi0/2
SWITCH_02>sho mac-addr addr 0201.0000.0000 Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- ----- 1 0201.0000.0000 DYNAMIC Fa0/5 Total Mac Addresses for this criterion: 1
SWITCH_02>sho mac-addr addr 0201.0000.0000 Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- ----- 1 0201.0000.0000 DYNAMIC Fa0/20 Total Mac Addresses for this criterion: 1
My questions are:
a) What is this mac address 0201.0000.0000? b) How do I proceed with troubleshooting this problem?
TIA and sorry for the long post.
JM