I am using a Netgear FSM7328S switch and have designated ports 19-24 as being part of VLAN # 3. I designated them all as untagged because I do not want them to switch traffic to any other port on the switch. I also removed them from the default, untagged, VLAN 1. My issue is that none of the ports 19-24 will communicate with eachother. My laptop plugged in with wireshark shows no switched traffic what so ever. Have I configured it wrong?

Edit: client workstations are being cabled directly to the untagged, vlan ports. If thats the case then are the frames from the clients being dropped because the ports will only switch tagged frames?

Thanks, D

  • did you follow a tutorial? Can you post your config output? – Bret Fisher Mar 9 '11 at 23:59
  • No tutorial. I just cobbled together as much knowledge as i thought I needed to get the job done. I'm by no means a network engineer. The setup is served via web gui so I don't believe i could post that. – Digital ink Mar 10 '11 at 0:17
  • I believe I may have found the answer. I neglected to set the PVID (Port Value ID?). From my understanding that is what initially determines the VLAN ID tagged to an incoming frame. That said I'm a little unclear on how the tagged/untagged status fits with that. – Digital ink Mar 10 '11 at 1:01

Think about it this way. Internally within the switch, all packets have a VLAN tag. When you mark a switch port untagged, it simply means that frames coming into the switch (ingress) are not expected to have a VLAN tag. In that case, the switch will give them the default VLAN tag 1 (which you deleted in your configuration) as the frame moves around within the switch. If there are other untagged switch ports (i.e. other ports in VLAN 1) then the frame can exit (egress) the switch.

When you set up tagging on the switch, you are specifying another VLAN (2 .. 4095) for all traffic coming in on a particular switch port. This means that the tagged traffic won't mix with the untagged traffic since they are in different VLANs.


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