Re: Mac flapping between Lan and Wan interface

lnacional · ‎05-22-2023

Hi, i have a issue between two sites of the company.

we have a main site (headquarters) and recently we connect a new site by a Lan to lan link. We trunk all vlans from main site to new site with a trunk port. And we having a problem with the clients of the new site, the mac address client flap between LAN ports (port-channels) and the wan port (gi 1/0/1).

attach diagrams.

logs:

I can't find any inconsistent configuration or loop that might be causing this behavior.

Thanks for you help

MHM Cisco World · ‎05-22-2023

you config the L2VPN with VLAN 10,11,12,30
it seem that there is mismatch in native vlan between HQ and branch
so we need to make sure that both side use same native vlan
also please share the
show stp for both side if you can

lnacional · ‎05-22-2023

Hi! how are you?

Thanks for the response.

REmote site:

=~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2023.05.22 16:40:23 =~=~=~=~=~=~=~=~=~=~=~=
login as: admin
Keyboard-interactive authentication prompts from server:
| Password:
End of keyboard-interactive prompts from server

SANTAFE_DC1-CORE#show spa
SANTAFE_DC1-CORE#show spanning-tree

VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 24577
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40961 (priority 40960 sys-id-ext 1)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0007
Spanning tree enabled protocol ieee
Root ID Priority 32775
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40967 (priority 40960 sys-id-ext 7)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0008
Spanning tree enabled protocol ieee
Root ID Priority 32776
Address 0023.04ee.bec8
Cost 4
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40968 (priority 40960 sys-id-ext
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0010
Spanning tree enabled protocol ieee
Root ID Priority 24586
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40970 (priority 40960 sys-id-ext 10)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0011
Spanning tree enabled protocol ieee
Root ID Priority 24587
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40971 (priority 40960 sys-id-ext 11)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0012
Spanning tree enabled protocol ieee
Root ID Priority 24588
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40972 (priority 40960 sys-id-ext 12)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0015
Spanning tree enabled protocol ieee
Root ID Priority 32783
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40975 (priority 40960 sys-id-ext 15)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0016
Spanning tree enabled protocol ieee
Root ID Priority 40976
Address f09e.6328.9700
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40976 (priority 40960 sys-id-ext 16)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/0/1 Desg FWD 4 128.1 P2p

--More--
VLAN0020
Spanning tree enabled protocol ieee
Root ID Priority 24596
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40980 (priority 40960 sys-id-ext 20)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0024
Spanning tree enabled protocol ieee
Root ID Priority 32792
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40984 (priority 40960 sys-id-ext 24)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0030
Spanning tree enabled protocol ieee
Root ID Priority 24606
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 40990 (priority 40960 sys-id-ext 30)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0050
Spanning tree enabled protocol ieee
Root ID Priority 24626
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 41010 (priority 40960 sys-id-ext 50)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0051
Spanning tree enabled protocol ieee
Root ID Priority 32819
Address 0023.04ee.be64
Cost 6
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 41011 (priority 40960 sys-id-ext 51)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0100
Spanning tree enabled protocol ieee
Root ID Priority 24676
Address 0023.04ee.be64
Cost 6
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 41060 (priority 40960 sys-id-ext 100)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0204
Spanning tree enabled protocol ieee
Root ID Priority 32972
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 41164 (priority 40960 sys-id-ext 204)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 4 128.528 P2p
Po11 Desg FWD 4 128.536 P2p
Po12 Desg FWD 4 128.544 P2p
Gi1/0/1 Root FWD 4 128.1 P2p

--More--
VLAN0234
Spanning tree enabled protocol ieee
Root ID Priority 33002
Address 0023.04ee.be64
Cost 5
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 41194 (priority 40960 sys-id-ext 234)
Address f09e.6328.9700
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi1/0/1 Root FWD 4 128.1 P2p

SANTAFE_DC1-CORE# exit

HQ is attached in txt

paul driver · ‎05-22-2023

Hello
Looks like you have a switching loop between Po11-po12-gig1/0/1, check the physical connections of the PCs for inconstancies (high utilisation, large stp transitions) if possible disable a port within the PC to break the loop.

show interface | include line|\/sec
show spanning-tree interface detail | in transitions

Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

MHM Cisco World · ‎05-22-2023

there is something in topology you share the HQ SW is vPC NSK and it connect to Branch via vPC PO ?
if Yes can you re-draw the topology again

lnacional · ‎05-23-2023

Hi, this is the core topology of HQ:

The Lan2Lan link is connected to CORE3 Switch.

MHM Cisco World · ‎05-24-2023

you run MST in HQ and PVST in branch ?