N9K - Mac Address Move alerts

Quintin.Mayo · ‎08-03-2021

Hi,

We notice a lot of L2FM-4L2FM mac address alerts within on Nexus 9k device. We found this link below explaining this behavior is caused by an L2 loop when the switch is receiving packets from the same host (source mac) on two or more different interfaces in the same vlan. Cisco recommendation is to apply the " mac address-table loop-detect port-down" command to take down the interface with lower interface index. My question is once a interface is shut down I assuming no service interruption will be experienced but at some time will the interface need to be enabled again? If someone can advise we would be greatly appreciated.

https://www.cisco.com/c/en/us/support/docs/ios-nx-os-software/nx-os-software/213906-nexus-9000-mac-move-troubleshooting-and.html

2021 Jul 28 14:44:28 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.0264 in vlan 44 has moved from Po3249 to Po3149
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.6055 in vlan 25 has moved from Po3149 to Po3249
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.0ee8 in vlan 1 has moved from Po3149 to Po3249
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.3099 in vlan 716 has moved from Po3149 to Po3249
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.9816 in vlan 460 has moved from Po3149 to Po3249
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.7998 in vlan 716 has moved from Po3149 to Po3249
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.5a99 in vlan 716 has moved from Po3249 to Po3149
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.0519 in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.0b12 in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:29 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.94be in vlan 915 has moved from Po3249 to Po3149
2021 Jul 28 14:44:30 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.fd70 in vlan 452 has moved from Po3149 to Po3249
2021 Jul 28 14:44:30 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.9e2b in vlan 919 has moved from Po3249 to Po3149
2021 Jul 28 14:44:30 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.2598 in vlan 448 has moved from Po3249 to Po3149
2021 Jul 28 14:44:30 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.4dab in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:30 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.4db2 in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:31 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.36b6 in vlan 1 has moved from Po3149 to Po3249
2021 Jul 28 14:44:31 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.67dc in vlan 716 has moved from Po3149 to Po3249
2021 Jul 28 14:44:31 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.0824 in vlan 918 has moved from Po3249 to Po3149
2021 Jul 28 14:44:31 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.7ae1 in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:31 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.5696.215b in vlan 5 has moved from Po3249 to Po3149
2021 Jul 28 14:44:32 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.03e6 in vlan 1 has moved from Po3149 to Po3249
2021 Jul 28 14:44:32 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.f71d in vlan 251 has moved from Po3149 to Po3249
2021 Jul 28 14:44:32 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.99c4 in vlan 1 has moved from Po3149 to Po3249
2021 Jul 28 14:44:32 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.150a in vlan 215 has moved from Po3149 to Po3249
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56ba.7106 in vlan 716 has moved from Po3149 to Po3249
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.60ca in vlan 251 has moved from Po3149 to Po3249
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.009b in vlan 1 has moved from Po3149 to Po3249
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.5696.4176 in vlan 716 has moved from Po3149 to Po3249
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.da3d in vlan 442 has moved from Po3149 to Po3249
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.6ac8 in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.3a5f in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:33 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.fe60 in vlan 919 has moved from Po3249 to Po3149
2021 Jul 28 14:44:34 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.8184 in vlan 915 has moved from Po3149 to Po3249
2021 Jul 28 14:44:34 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.07c9 in vlan 456 has moved from Po3149 to Po3249
2021 Jul 28 14:44:34 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.3caa in vlan 1 has moved from Po3249 to Po3149
2021 Jul 28 14:44:35 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568f.20e9 in vlan 998 has moved from Po3249 to Po3149
2021 Jul 28 14:44:35 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.568d.9612 in vlan 251 has moved from Po3249 to Po3149
2021 Jul 28 14:44:35 RT-N9K %L2FM-4-L2FM_MAC_MOVE2: Mac 0050.56be.4d42 in vlan 1 has moved from Po3149 to Po3249

Thanks,

Elliot Dierksen · ‎08-03-2021

The root cause here is that you have some kind of layer 2 looping. I think you would be better off trying to resolve the loop rather than trying to mask the error messages that the loop is causing.

Jo49201 · ‎08-09-2021

Elliot answer should be the was to go.

We had a similar issue, where an old Core switch was sending mac addresse that was not connected it it.
Probably seeing those mac from arp.
We were having the issue and receiving disable learn mac address for 2 minutes.

On our side we saw random mac address from our network.