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Trunk Port Not Carrying Vlan Information


I am using a 3500 switch which is connected to my Core (L3 Switch). i have made the fast Ethernet port 15 as a trunk port and have created a vlan interface.

my problem is that my trunk port and interface valn both are showing up but i am neighther able to ping the core switch nor the vlan information on the core is populating on the access switch.find below the config and please help me getting this up.

Interface FastEthernet0/15

duplex full

speed 100

switchport trunk encapsulation dot1q

switchport trunk native vlan 200

switchport mode trunk

Int Vlan 200

interface VLAN200

ip address

no ip directed-broadcast

no ip route-cache


Re: Trunk Port Not Carrying Vlan Information

Hi Sami,

The reason your trunk port not carrying vlan information of vlan 200 is because native vlans send their frames untagged on trunk links so identification and classification is lost.

Its always good praticse to keep the native vlan the default vlan1.

To allow dot1q to tag native vlans use this command to enable it.

Switch (config)# vlan dot1q tag native

Hope this helps



Re: Trunk Port Not Carrying Vlan Information

Can you post the output of sh VTP status form both switches & output of sh int fa 0/15 switchport


New Member

Re: Trunk Port Not Carrying Vlan Information

Hi Rajnikant,

Thanks a lot for the information it's really very helpfull.

but would alos like to tell you that the same thnk started working later when i created a vlan 200 in the vlan database any clue how this worked?

New Member

Re: Trunk Port Not Carrying Vlan Information

I think, you are running VTP transparent mode on your core switch. For vtp transparent mode, you need to create required vlan in access switch first in order to connect to core switch.

New Member

Re: Trunk Port Not Carrying Vlan Information

Could you also show the configuration of the core swith trunk port.

Outputs from both the core switch and local switch would also be useful.

e.g. show interfaces fastethernet 0/15 trunk


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