Hello to forum,
I have network with 100 switches - 8x L3 switches with 10G ring.
On main L3 switch is logged a lot of host flapping issues - more than 4500 in a day.
Main switch version:
Cisco IOS Software, IOS-XE Software, Catalyst 4500 L3 Switch Software (cat4500e-UNIVERSALK9-M), Version 03.02.00.SG RELEASE SOFTWARE (fc4)
For example:
show logging
Oct 23 12:33:43: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:33:44: %C4K_EBM-4-HOSTFLAPPING: Host 20:02:AF:BA:8A:34 in vlan 119 is moving from port Po3 to port Po4
Oct 23 12:33:48: %C4K_EBM-4-HOSTFLAPPING: Host DC:2B:61:03:CA:C1 in vlan 119 is moving from port Po4 to port Po3
Oct 23 12:33:48: %C4K_EBM-4-HOSTFLAPPING: Host 50:CC:F8:4C:77:F4 in vlan 119 is moving from port Po4 to port Po3
Oct 23 12:33:49: %C4K_EBM-4-HOSTFLAPPING: Host 50:CC:F8:4C:77:F4 in vlan 119 is moving from port Po3 to port Po4
Oct 23 12:33:52: %C4K_EBM-4-HOSTFLAPPING: Host 14:5A:05:F2:10:7A in vlan 118 is moving from port Po3 to port Po4
Oct 23 12:34:00: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:34:00: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:34:03: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:34:06: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:34:09: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:34:15: %C4K_EBM-4-HOSTFLAPPING: Host 70:73:CB:67:8C:E0 in vlan 118 is moving from port Po3 to port Po4
Oct 23 12:34:16: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:34:18: %C4K_EBM-4-HOSTFLAPPING: Host 5C:0A:5B:3A:83:CE in vlan 202 is moving from port Po4 to port Po3
Oct 23 12:34:23: %C4K_EBM-4-HOSTFLAPPING: Host 00:26:52:53:3C:C0 in vlan 1 is moving from port Gi2/6 to port Te1/1
Oct 23 12:34:23: %C4K_EBM-4-HOSTFLAPPING: Host 00:26:52:53:3C:C0 in vlan 1 is moving from port Te1/1 to port Gi2/6
Oct 23 12:34:40: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:34:48: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:34:57: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:35:04: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:35:13: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:35:14: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:35:14: %C4K_EBM-4-HOSTFLAPPING: Host D8:57:EF:F9:67:C1 in vlan 118 is moving from port Po3 to port Po4
Oct 23 12:35:16: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:35:22: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:35:40: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:35:45: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:35:47: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:35:47: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:35:48: %C4K_EBM-4-HOSTFLAPPING: Host 9C:04:EB:98:A4:23 in vlan 119 is moving from port Po3 to port Po4
Oct 23 12:35:50: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:35:51: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:36:03: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:36:03: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:36:08: %C4K_EBM-4-HOSTFLAPPING: Host 40:B3:95:3D:9E:BB in vlan 119 is moving from port Po3 to port Po4
Oct 23 12:36:20: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:36:21: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
Oct 23 12:36:21: %C4K_EBM-4-HOSTFLAPPING: Host 20:54:76:1E:E4:0C in vlan 118 is moving from port Po3 to port Po4
Oct 23 12:36:21: %C4K_EBM-4-HOSTFLAPPING: Host D8:57:EF:F9:67:C1 in vlan 118 is moving from port Po4 to port Po3
Oct 23 12:36:23: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Te1/1 to port Gi2/9
Oct 23 12:36:24: %C4K_EBM-4-HOSTFLAPPING: Host 00:24:8C:B9:05:C7 in vlan 2 is moving from port Gi2/9 to port Te1/1
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I think, that cannot be problem with loop some PCs in network, maybe some STP problem - or SW bug in IOS?
Anybody can help with this?
Best Regards,
Stepan
