07-29-2010 06:45 AM - edited 03-06-2019 12:14 PM
Good luck with this one. We are getting a native VLAN mismatch and the native VLAN is the same on both 3750's:
We are getting the following logging on 3750-1:
Jul 29 01:12:43: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on
GigabitEthernet1/0/1 (620), with 3750-2 GigabitEthernet1/0/12 (1).
Jul 29 01:13:43: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on
GigabitEthernet1/0/1 (620), with Trent_Fibre GigabitEthernet1/0/12 (1).
Jul 29 01:14:43: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on
GigabitEthernet1/0/1 (620), with Trent_Fibre GigabitEthernet1/0/12 (1).
Jul 29 01:15:43: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on
GigabitEthernet1/0/1 (620), with Trent_Fibre GigabitEthernet1/0/12 (1).
Jul 29 01:16:43: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on
GigabitEthernet1/0/1 (620), with Trent_Fibre GigabitEthernet1/0/12 (1).
Here is the config for 3750-1:
VLAN Name Status Ports
---- -------------------------------- --------- ------------------------------
1 default active Fa1/0/3, Fa1/0/4, Fa1/0/5
Fa1/0/6, Fa1/0/8, Fa1/0/9
Fa1/0/10, Fa1/0/11, Fa1/0/12
Fa1/0/13, Fa1/0/14, Fa1/0/15
Fa1/0/16, Fa1/0/17, Fa1/0/18
Fa1/0/19, Fa1/0/20, Fa1/0/21
Fa1/0/22, Fa1/0/23, Gi1/0/2
72 VLAN0072 active Fa1/0/1, Fa1/0/2
202 VLAN0202 active Fa1/0/24
620 Data active Fa1/0/7
621 Voice active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 0 0
72 enet 100072 1500 - - - - - 0 0
202 enet 100202 1500 - - - - - 0 0
620 enet 100620 1500 - - - - - 0 0
621 enet 100621 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
------------------------------------------------------------------------------
Primary Secondary Type Ports
------- --------- ----------------- ------------------------------------------
3750-1#
3750-1#
3750-1#
3750-1#sh int trunk
Port Mode Encapsulation Status Native vlan
Gi1/0/1 on 802.1q trunking 1
Port Vlans allowed on trunk
Gi1/0/1 1-4094
Port Vlans allowed and active in management domain
Gi1/0/1 1,72,202,620-621
Port Vlans in spanning tree forwarding state and not pruned
Gi1/0/1 1,72,202,620-621
Here is the config on 3750-2:
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Gi1/0/5, Gi1/0/6, Gi1/0/7
Gi1/0/8, Gi1/0/9, Gi1/0/10
Gi1/0/11
620 Data active
621 Voice active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 0 0
620 enet 100620 1500 - - - - - 0 0
621 enet 100621 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
------------------------------------------------------------------------------
Primary Secondary Type Ports
------- --------- ----------------- ------------------------------------------
3750-2#
3750-2#
3750-2#sh int trunk
Port Mode Encapsulation Status Native vlan
Gi1/0/1 auto n-802.1q trunking 1
Gi1/0/2 auto n-802.1q trunking 1
Gi1/0/3 on 802.1q trunking 1
Gi1/0/4 on 802.1q trunking 1
Gi1/0/12 on 802.1q trunking 1
Port Vlans allowed on trunk
Gi1/0/1 1-4094
Gi1/0/2 1-4094
Gi1/0/3 1-4094
Gi1/0/4 1-4094
Gi1/0/12 1-4094
Port Vlans allowed and active in management domain
Gi1/0/1 1,620-621
Gi1/0/2 1,620-621
Gi1/0/3 1,620-621
Gi1/0/4 1,620-621
Gi1/0/12 1,620-621
Port Vlans in spanning tree forwarding state and not pruned
Gi1/0/1 1,620-621
Gi1/0/2 1,620-621
Gi1/0/3 1,620-621
Gi1/0/4 1,620-621
Gi1/0/12 1,620-621
Please let me know what you think.
07-29-2010 06:55 AM
Hello,
Can you please post the running configuration from both ports in question
here?
Regards,
NT
07-29-2010 07:19 AM
interface GigabitEthernet1/0/1
description link to fibre switch
switchport trunk encapsulation dot1q
switchport mode trunk
end
interface GigabitEthernet1/0/12
switchport trunk encapsulation dot1q
switchport mode trunk
end
07-29-2010 07:45 AM
Hello,
Thanks for the outputs. Are you still getting those error messages or did
they stop? If you are not getting those error messages anymore, can you
check your logs to see if somebody made any changes to the configuration
during the period?
Regards,
NT
07-29-2010 07:57 AM
Actually, dont worry. I double checked the time and date
again and it was when we made some configuration changes. Thanks for your help.
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