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VLAN Filters

When I apply a port-filter or a map-rule which is filtering on a VLAN ID, I don’t see any frames coming out the tool port. Why is that?

Answer: By default, data switch SPAN/Mirror ports remove the VLAN header before the frames are sent out of the SPAN/Mirror ports. The frames coming into the GigaVUE network ports do not have the VLAN ID information in them so the frames will not match the filter/map-rule and will be discarded. The solution to this is to:

  1. Delete the SPAN/Mirror session.
  2. Configure the SPAN/Mirror port type as a trunk (contact the switch vendor for the instructions on how to do this).
  3. Create the SPAN/Mirror session again.

Once these steps are complete, the GigaVUE’s tool port counters should start incrementing to indicate that frames are successfully being forwarded. This confirms that the SPAN/Mirror port is now configured properly.

Sometimes, even though the GigaVUE’s tool port counters are incrementing, the frames cannot be seen in the Network Analyzer Tool. The most common reason for this is that many of the Network Analyzer Tools need an updated Network Interface Card (NIC) driver installed which can recognize the VLAN header information. If you suspect this may be the problem, please contact the respective manufacturer for the appropriate driver.

Also the NIC must be configured for Promiscuous Mode in order to capture the frames.

For Technical Support contact Gigamon Systems via email at support@gigamon.com or call 408-263-2024