12-01-2021 02:26 AM
Hello I have problem with loop guard and flapping port.
Short info about my network .
I have 44 switch connect in spanning tree MSTP.
I was configure 3 instances .
I deleted the ip switch addresses and changed the vlan names. Vlan X is from instance 1 and Vlan Y is from instance Y
When I change Vlan in instance 3 (adding new Vlan) have this info
My question is:
why if I change something in the instanceMST3, something changes is MST1 and Vlany from the MST1 flapping port between switches?
10:36:15 | Local7 | Critical | 1851: .Dec 1 10:38:05.857: %SPANTREE-2-LOOPGUARD_BLOCK: Loop guard blocking port GigabitEthernet1/1 on MST1. | |
10:35:35 | Local7 | Warning | 1713: .Dec 1 10:37:25.331: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/26 and port Gi1/25 | |
10:35:35 | Local7 | Warning | 998: .Dec 1 10:37:25.342: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1698: .Dec 1 10:37:25.338: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/26 and port Gi1/25 | |
10:35:35 | Local7 | Warning | 1678: .Dec 1 10:37:25.337: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/26 and port Gi1/24 | |
10:35:35 | Local7 | Warning | 1838: .Dec 1 10:37:25.401: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/27 and port Gi1/25 | |
10:35:35 | Local7 | Warning | 1850: .Dec 1 10:37:25.365: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1837: .Dec 1 10:37:25.317: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/25 and port Gi1/27 | |
10:35:35 | Local7 | Warning | 1836: .Dec 1 10:37:25.275: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/25 and port Gi1/27 | |
10:35:35 | Local7 | Warning | 1849: .Dec 1 10:37:25.331: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1848: .Dec 1 10:37:25.264: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1979: .Dec 1 10:37:25.407: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/26 and port Gi1/27 | |
10:35:35 | Local7 | Warning | 1978: .Dec 1 10:37:25.250: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/26 and port Gi1/27 | |
10:35:35 | Local7 | Warning | 1977: .Dec 1 10:37:25.250: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/27 and port Gi1/26 | |
10:35:35 | Local7 | Warning | 1873: .Dec 1 10:37:25.326: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/2 and port Gi1/3 | |
10:35:35 | Local7 | Warning | 1872: .Dec 1 10:37:25.291: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/2 and port Gi1/3 | |
10:35:35 | Local7 | Warning | 1745: .Dec 1 10:37:25.351: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1744: .Dec 1 10:37:25.317: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1871: .Dec 1 10:37:25.256: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/3 and port Gi1/2 | |
10:35:35 | Local7 | Warning | 1743: .Dec 1 10:37:25.250: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1734: .Dec 1 10:37:25.378: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1733: .Dec 1 10:37:25.277: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 1732: .Dec 1 10:37:25.244: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/1 and port Gi1/2 | |
10:35:35 | Local7 | Warning | 2429: .Dec 1 10:37:25.370: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/3 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 2428: .Dec 1 10:37:25.324: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/3 and port Gi1/1 | |
10:35:35 | Local7 | Warning | 2427: .Dec 1 10:37:25.178: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/3 and port Fa1/12 | |
10:35:35 | Local7 | Warning | 1724: .Dec 1 10:37:25.403: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/1 and port Gi1/2 | |
10:35:35 | Local7 | Warning | 1723: .Dec 1 10:37:25.370: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/1 and port Gi1/2 | |
10:35:35 | Local7 | Warning | 1722: .Dec 1 10:37:25.269: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/1 and port Gi1/2 | |
10:35:15 | Local7 | Warning | 1080: .Dec 1 10:37:05.745: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.a54c in vlan X is flapping between port Gi1/2 and port Gi1/1 | |
10:35:15 | Local7 | Warning | 1079: .Dec 1 10:37:05.678: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/1 and port Gi1/2 | |
10:35:15 | Local7 | Warning | 1078: .Dec 1 10:37:05.511: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/1 and port Gi1/2 | |
10:35:14 | Local7 | Warning | 2404: .Dec 1 10:37:04.691: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f713.b12e in vlan X is flapping between port Gi1/27 and port Gi1/25 | |
10:35:14 | Local7 | Warning | 2403: .Dec 1 10:37:04.621: %SW_MATM-4-MACFLAP_NOTIF: Host 000a.f733.17fe in vlan X is flapping between port Gi1/27 and port Gi1/25 | |
10:35:13 | Local7 | Warning | 1832: .Dec 1 10:36:56.515: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/26 and port Gi1/28 | |
10:35:13 | Local7 | Warning | 1830: .Dec 1 10:36:51.223: %SW_MATM-4-MACFLAP_NOTIF: Host 000e.c6cd.bfc7 in vlan Y is flapping between port Gi1/26 and port Gi1/28 | |
10:35:11 | Local7 | Warning | 1670: .Dec 1 10:37:01.380: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:06 | Local7 | Warning | 2402: .Dec 1 10:36:56.525: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/26 and port Gi1/27 | |
10:35:06 | Local7 | Warning | 1669: .Dec 1 10:36:56.591: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/1 and port Gi1/2 | |
10:35:06 | Local7 | Warning | 1658: .Dec 1 10:36:56.599: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:06 | Local7 | Warning | 1669: .Dec 1 10:36:56.414: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:06 | Local7 | Warning | 1666: .Dec 1 10:36:56.527: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/1 and port Gi1/2 | |
10:35:06 | Local7 | Warning | 1640: .Dec 1 10:36:56.495: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:06 | Local7 | Warning | 960: .Dec 1 10:36:56.461: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:04 | Local7 | Warning | 1077: .Dec 1 10:36:54.236: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:01 | Local7 | Warning | 2401: .Dec 1 10:36:51.230: %SW_MATM-4-MACFLAP_NOTIF: Host 0010.189e.3684 in vlan Y is flapping between port Gi1/26 and port Gi1/27 | |
10:35:01 | Local7 | Warning | 2400: .Dec 1 10:36:51.094: %SW_MATM-4-MACFLAP_NOTIF: Host 000e.c6cd.bfc7 in vlan Y is flapping between port Gi1/26 and port Gi1/27 | |
10:35:00 | Local7 | Warning | 1072: .Dec 1 10:36:51.082: %SW_MATM-4-MACFLAP_NOTIF: Host 000e.c6cd.bfc7 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:00 | Local7 | Warning | 955: .Dec 1 10:36:51.033: %SW_MATM-4-MACFLAP_NOTIF: Host 000e.c6cd.bfc7 in vlan Y is flapping between port Gi1/2 and port Gi1/1 | |
10:35:00 | Local7 | Warning | 1640: .Dec 1 10:36:51.094: %SW_MATM-4-MACFLAP_NOTIF: Host 000e.c6cd.bfc7 in vlan Y is flapping between port Gi1/2 and port Gi1/1 |
BR
12-01-2021 02:40 AM - edited 12-01-2021 02:42 AM
Hello
@bartosz.wrzosek wrote:
My question is:
why if I change something in the instanceMST3, something changes is MST1 and Vlany from the MST1 flapping port between switches?
Absolutely it would as you can see from your logging, you cannot just prune vlans in an mst instance, In MST, STP is running per instance not per vlan, so the changes you make need to be made throughout your estate, not just on one particular switch and instance on that switch.
12-01-2021 03:52 AM
I don't think we understood each other. I change configurations on all switches. And during this change process, I get these logs.
For me it is strange that I change the configuration of instance 3 and in the logs I have info that something has changed in instance 1.
12-01-2021 01:05 PM
Hello
@bartosz.wrzosek wrote:
For me it is strange that I change the configuration of instance 3 and in the logs I have info that something has changed in instance 1.
I would expect to see some stp disruption because those mst instances (1,2,3) would not have parity with each other on the trunks interconnects at the time of your changes.
12-01-2021 10:38 PM - edited 12-05-2021 10:28 PM
Could you please develop your thought Why is there no parity? More details
I don't understand why the odd number of instances affects this error
BR
12-01-2021 04:05 AM
follow
12-08-2021 03:55 PM
https://www.youtube.com/watch?v=q-cNoq50Kxo
min 25, the expert talk about the add of VLAN and it effect on MST.
please watch video and I hope it help you why you get TCN for add one VLAN.
12-08-2021 10:55 PM
Hello
"min 25, the expert talk about the add of VLAN and it effect on MST."
I understand that you are suggesting that must be 25 instances? Did I understand you well?
Thanks for the video, I am analyzing them, I will let you know when I have more questions.
BR
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