major issue

The docking station are causing a problem on our network, They memorize a mac address and shut down the ports on a Cisco switch with port security, some times not on the port that it is connected to but one on the same or trunked switch

Hi Charles-

Thanks for posting with your issue, I’ll be happy to help!

As you probably know, the mac address is a permanent identifier for a network device, so I’m unsure what you mean when you mention that our docking stations are memorizing a mac address- this sounds normal to me.

If you have enabled mac filtering on the Cisco device, only known mac addresses will be allowed to connect: could it be that these new devices that aren’t working aren’t on your white list for mac address authentication?

Please let me know if there is something I’m missing. If you are also able to verify what model of docking station you have that would be helpful:

http://plugable.com/products#USB 3.0 Computer Docking Stations

Best wishes-

Jeff Everett
Plugable Technologies

The port replicator is sending some packets with the MAC address of the default router in the source field. The switch then thinks the default router is located on that port instead of the uplink port. This would not be a major problem as it is auto-correcting when the default router sends traffic to the switch, but we are using Port Security so the invalid source address from the port replicator is kept on the port, disabling that port and other ports on the same switch and vlan.

The port replicator is sending some packets with the MAC address of the default router in the source field. The switch then thinks the default router is located on that port instead of the uplink port. This would not be a major problem as it is auto-correcting when the default router sends traffic to the switch, but we are using Port Security so the invalid source address from the port replicator is kept on the port, disabling that port and other ports on the same switch and vlan.

Hi Charles-

Thanks so much for getting back to us with these the extra details!

I’d love to be able to try and replicate and solve this issue, however some other information will be necessary to be able to do this. Primarily, I need to be clear on which of our products you are using.

Can you please verify which Plugable product you have? Our products are listed here: http://plugable.com/products

I think that you have the UD-3000, listed here http://plugable.com/products/UD-3000 , however since different devices use different networking chips it’s crucial that I understand which device you have to be able to help.

If you’re also able to share some details of how you’re checking these packets (wireshark, etc), and post a sample of a packet from the adapter in question with the incorrect mac, this would also be very helpful.

Best wishes-

Jeff Everett
Plugable Technologies

Hi Charles-

If you are indeed using the UD-3000, the latest DisplayLink driver (7.2m1) resolves a similar issue, although this is a brand new version so please let us know if you hit any other issues.

http://www.displaylink.com/support/do…

I hope this helps, and will be curious to hear either way.

Best wishes-

Jeff

Before we received the fix issue we put a USB-nic adaptor on the port replicator that has its own driver and it is working with no issues, It seems the problem is in the nic driver of the port replicator. Will the fix that was sent to me solve this issue.

Hi Charles-

As best I understand the issue you’ve described, yes.

The specific issue that was listed as resolved in DisplayLink’s release notes for the 7.2M1 driver is
“Ethernet packets with incorrect MAC address being sent from DisplayLink dock.
(14954, 15123)”

The full release notes are here: http://displaylinkreleasenotes.s3.ama…

I’ll be curious to hear if this helps. Please let me know if you have any other questions.

Best wishes-

Jeff Everett
Plugable Technologies