capture id vlan with sniffer

[Jose Salazar]

Hello everyone,

I configured several vlans and I configured a session monitor from port gi0/7 to gi0/6

I ran wirehsark in order to capture the vlan ID but I don't see any parameter where the host is tagged with the vlan. The vlan I want to confirm is working is the vlan id 40 which was assign into the port gi0/7

what do you recommend?

thanks

[Reza Sharifi]

Hi,

If the ports are configured as access ports, you will not see vlan tags because the ports are not configured as dot1.q

If you are trying to see the vlan id than make sure the port where the Wireshark is connected is not in any vlan.

from Wireshark document:

You can use a tap or span a port to listen to VLAN traffic. In order to span the traffic to or from devices in a VLAN, span the port of a device in the VLAN. Define the destination port as the one that Wireshark is connected to on the switch. In order to see VLAN tags, do not configure Wireshark’s interface connected to the switch as a member of a VLAN.There is still no guarantee you will be able to see VLAN tags, however, because different operating systems and drivers handle VLAN tags in different manners.

HTH