Intel 82541GI NIC comes up at 10mbps on one port

[Roger Heflin]

Mikkel L. Ellertson wrote:
> Sam Varshavchik wrote:
>> Mikkel L. Ellertson writes:
>>
>>> Try using ethtoolto lock the port to 100 Mbs Full Duplex. It is
>>> probably that the two do not handshake correctly to set the faster
>>> speed. If I remember correctly, that was one of the things that the
>>> exact protocol was not specified, so not all hardware works correctly.
>> I should've mentioned that I tried that too. By itself "speed 100" has
>> no effect, and the link still comes up auto-negotiated at 10mbps.
>>
>> If I use "speed 100 autoneg off" the '100mbps' LED indicator on the
>> router does come on, but the NIC is completely dead and does not respond
>> to pings. Adding an explicit "duplex half" or "duplex full" to the mix
>> makes no difference. I've also tried unplugging and plugging the cable
>> after forcing the speed to 100. The router itself, as I mentioned, has
>> no configurable knobs, just the ports and nothing else. I'm guessing
>> that even after forcing the speed to 100mbps, the router wants to
>> negotiate something.
>>
>> Sorting through the documentation for e1000.ko, there's a module option
>> to limit advertised link speeds to 100 mbps only, that is,
>> auto-negotiation remains on but the card won't advertise 10 mbps speed.
>> After enabling that option, the port does not come up at all.
>>
> Well, there goes the simple fix.
> 
> I would not expect "configuration knobs" on the router. There should
> be configuration web pages when you open the routers address in a
> web browser. http://192.168.0.1 or http://192.168.1.1 is the default
> address, if I remember right. It is in the router manual. But it
> probably does not have anything to help you with your problem.
> 
> Mikkel
> 

In the past having one side negotiating and not the other got
generally bad results (usually 10-half duplex was the default
if negotiating failed, no matter what the other side was forced
to-and things worked really really bad).

On my linksys router (with the add-on linux DD-WRT software) I
can set each port to autoneg/100/FD, so it may be possible on
a standard router with the standard linksys router software.

                        Roger