[realtek] rtl8139 problem
Sat Aug 31 15:31:01 2002
On Sat, 31 Aug 2002, Roberto De Leo wrote:
> I have 2 Linux Boxes connected through a twisted class 5 cable.
Home-made or commercially made?
You likely have mis-paired the cable. The pairing is not the obvious
1+2,3+4,5+6,7+8, it should be 1+2,3+6,4+5,7+8
> Here is my problem: when the NE2k was connected I could tranfer files
> from one PC to the other at the regular 10Mbps speed.
> Now that the cards are both 10/100 and so they could reach the nice
> speed of 100Mbps I get a much worse result: on the path 8129->8139
> I reach at most 1.4Kb/s [measured through a ncftp download], while
> on the opposite trajectory the trasfer speed does not pass .4Kb/s!!!
This sounds like corrupted packets. You would get much higher speeds
even with a duplex mismatch.
> How can it be possible that the cards negotiate a 100Mbps speed but then
> behave so ridicolously bad?
Negotiation takes place at 10baseT speed, and even mis-paired cables
will work at that speed.
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