(PVID) inconsistency *PVID_Inc Issue

Hello,

Issue: Vlan 1 is in (PVID) inconsistency state on the Core switch for
some access switches trunk ports.

Native Vlan is 1 (same on all the switches)

Find the output below:

Core Switch (6513)

SW-Core#sh spanning-tree inconsistentports

Name Interface Inconsistency
-------------------- ---------------------- ------------------
VLAN0001 GigabitEthernet11/1 Port VLAN ID Mismatch
VLAN0001 GigabitEthernet11/2 Port VLAN ID Mismatch

SW-Core#sh spanning-tree vlan 1

Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi11/1 Desg BKN*4 128.1281 P2p *PVID_Inc
Gi11/2 Desg BKN*4 128.1282 P2p *PVID_Inc

SW-Core#sh logging

%SPANTREE-SP-2-RECV_PVID_ERR: Received BPDU with inconsistent peer
vlan id 1 on GigabitEthernet11/2 VLAN1012.

%SPANTREE-SP-2-BLOCK_PVID_PEER: Blocking GigabitEthernet11/2 on
VLAN0001. Inconsistent peer vlan.

SW-Core#sh spanning-tree vlan 1 detail | inc 11/2
 Port 1282 (GigabitEthernet11/2) of VLAN0001 is broken (Port VLAN ID Mismatch)

BPDU: sent 0, received 1173 *************

SW-GF-BB1#sh inter trunk

Port Vlans in spanning tree forwarding state and not pruned

Gi11/2 100-105

============================

Access Switch(2960) :

SWITCH 1 (which is connected through 11/2 of CORE SW)

switch01#sh spanning-tree vlan 1

VLAN0001
  Spanning tree enabled protocol ieee
  Root ID Priority 49153
             Address 0018.18aa.aaaa
  ******* This bridge is the root **********
             Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

  Bridge ID Priority 49153 (priority 49152 sys-id-ext 1)
             Address 0018.18aa.aaaa
             Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300
  Uplinkfast enabled

Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/21 Desg FWD 3004 128.21 P2p
Gi0/22 Desg FWD 3004 128.22 P2p

" VLAN 1 is root bridge "

Whereas all other Vlans are working normal.

VLAN0100
  Spanning tree enabled protocol ieee
  Root ID Priority 100
             Address 0014.f1bb.bbbb
             Cost 3004
             Port 21 (GigabitEthernet0/21)
             Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

  Bridge ID Priority 49252 (priority 49152 sys-id-ext 100)
             Address 0018.18aa.aaaa
             Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
             Aging Time 300
  Uplinkfast enabled

Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/21 Root FWD 3004 128.21 P2p
Gi0/22 Altn BLK 3004 128.22 P2p

On the Core switch:

SW-Core#sh inter trunk
Port Vlans in spanning tree forwarding state and not pruned
Gi11/2 100-105

I have fixed this issue by forcefully allowing under trunk interface(
even though this the default):

switchport trunk allowed vlan 1-4094

After applying the above command, Core switch output changed to and
the PVID_Inc error went away :

SW-Core#sh inter trunk
Port Vlans in spanning tree forwarding state and not pruned
Gi11/2 1,100-105

================================

I have solved this issue on 3560 Access Switch by applying:

SW-3560(config)#vlan dot1q tag native

Core Switch Logs :

 %SPANTREE-SP-2-UNBLOCK_CONSIST_PORT: Unblocking GigabitEthernet11/1
on VLAN0001. Port consistency restored.

I have many access switches with the same configuration but WHY I am
getting this issue only on some switches. I want to know why this
problem is random in nature (occurring on only some switches).

Secondly "vlan dot1q tag native" is not supported some of the access
switches(2960) but this command has applied on the core switch. Should
I remove it from the Core switch or keep it there? What is the best
practice? But other access switches are working properly without "vlan
dot1q tag native" command.

How can I fix this issue without applying "switchport trunk allowed
vlan 1-4094".

This problem is not solved by SHUT/NOSHUT under the trunk interfaces.

All switching are working in PVST+ mode

Regards,
Anser

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Received on Sun Nov 01 2009 - 12:59:03 ART