Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

We just bought two of these gigabit switches from Trendnet. They seem to function except for some laptops (no clear connection - different devices, OSs, chipsets, cables etc) don't work. Desktops seem unaffected, as well as VoIP phones, and other switches.

This problem occurred with both switches. I can't imagine this is an issue with this device as it has generally positive reviews all over the web. It's completely unmanaged so there's not much I can check. The status LEDs indicate all is well.

Anybody have any ideas about what could be going on or how I could attempt to diagnose?

share|improve this question
I discovered the answer. Flow Control. I'm not sure why but on the laptops if flow control is enabled they will be consistently unable to achieve any connectivity. As soon as I turn flow control on the NIC off everything works as it should. On desktops flow control doesn't seem to be an issue and can be left enabled but on the laptops it must be off. – Josh May 4 '12 at 13:45
Pleas post your answer as an Answer. You will be able to mark it as the correct answer after a short-ish waiting period. Thank you! – Chris S May 4 '12 at 14:07

I've seen certain older laptops that didn't have good auto sense to tell when to change to and from crossover mode. Might try a crossover cable to see if it helps. Not sure what else to look at.

share|improve this answer
They're not older laptops, they have gigabit NICs and the switch ports are all auto-mdix. – Josh May 4 '12 at 12:52

I have also seen many issues with older machines that have issues with autodetect for the speed and duplex. I would try tweaking the Speed and duplex settings of the NIC card on the affected devices. Usually this is a problem when the devices don't match. 1 is set at auto and the other is hard set at 100/full or vice versa.

share|improve this answer
The switch ports are auto-mdix, and I've tried setting NICs to auto, or set speeds of 10, 100, or 1gig. The switch has LED indicators which show the speed of the attached host and these correctly show when the NIC is set to 100, or 1gig, but still no traffic! – Josh May 4 '12 at 12:52
up vote 0 down vote accepted

Clients on this switch must have flow control disabled.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.