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New Member

all vlan cross the trunk

Hi Experts

i have to Switches connected together via trunk,on the trunk i allowed 5 vlan to cross  the trunk (Port-channel 4)  from SW1 to SW2 but on sw2 i found all vlan there?what could be the problem

thanks

6 REPLIES
New Member

all vlan cross the trunk

Hi Ibrahim,

If i understand you right, you have more than five vlans, and you have allowed 5 vlans on the trunk, but you are seeing all your other vlans??

If so, Are you running VTP on your switch???

Or you can post your config and i'll have a look.

Regards,

TP

New Member

all vlan cross the trunk

Hi Terrence

If i understand you right, you have more than five vlans, and you have  allowed 5 vlans on the trunk, but you are seeing all your other vlans??

Answer:YES

yes VTP is ruuning

thanks

New Member

all vlan cross the trunk

Hi Ibrahim,

Can you post the "sh vtp stat" on both our switches, that is switch 1 and 2.

Thanks

New Member

all vlan cross the trunk

Hi Terrence

W1#show vtp status

VTP Version           : 2

Configuration Revision     : 50

Maximum VLANs supported locally : 250

Number of existing VLANs    : 50

VTP Operating Mode       : Server

VTP Domain Name         : NETW

VTP Pruning Mode        : Disabled

VTP V2 Mode           : Disabled

VTP Traps Generation      : Disabled

MD5 digest           : 0x1E 0xED 0x19 0x49 0x0F 0x37 0x65 0x64

SW2#show vtp status

VTP Version           : 2

Configuration Revision     : 50

Maximum VLANs supported locally : 250

Number of existing VLANs    : 50

VTP Operating Mode       : Server

VTP Domain Name         : NETW

VTP Pruning Mode        : Disabled

VTP V2 Mode           : Disabled

VTP Traps Generation      : Disabled

MD5 digest           : 0x1E 0xED 0x19 0x49 0x0F 0x37 0x65 0x64

Purple

all vlan cross the trunk

  You are getting vtp and what is allowed across the trunks mixed up 2 different things.  VTP will propagate the vlans configured on the vtp server  across all vtp client switches.  Just because you see them in a show vlan command does not mean the traffic for all those vlans are allowed across the trunk.Only traffic from the vlans  that are in the " switchport trunk allowed " command are allowed across the vlan .

New Member

all vlan cross the trunk

Ibrahim,

If I understand correctly, you don't want vlans outside of the 5 you've allowed on the trunk to be present in the available vlan list on switch 2, correct?

If thats the case, you will need to enable VTP pruning on the switches.  From the vtp status output, I see that both are set to operate in server mode.  You'll need to change the downstream switch so that is is a client.

HTH

Jason

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