[eepro100] Linux Full Duplex

Donald Becker becker@scyld.com
Thu, 25 May 2000 11:47:02 -0400 (EDT)


On Wed, 24 May 2000, Leonardo Rodrigues wrote:

> zeus kernel: eth0: Intel EtherExpress Pro 10/100 at 0xfce0,
> 00:A0:C9:83:07:9E, IRQ 5
...
> 	Questions: Is this board 100Mbps FULL duplex capable ?

Yes.

> If the answer is
> yes, how can I enable it ? The NIC is plugged on a Cisco 100Mbit FULL
> duplex capable switch, with autonegotiation, but Linux isnīt getting full
> duplex automatically on, as its supposed to be.

It should negotiate full duplex automatically.
Run 'mii-diag' or 'mii-diag --watch' to see the status
   http://www.scyld.com/diag/index.html

If you have forced full duplex on the Cisco, you have disabled
autonegotiation.  Turn it back on.

If your Cisco switch does not properly autonegotiate, promise yourself that
you will never again buy substandard equipment just because the high price
tag makes you think it will work properly.

Then put stickers on the equipment, noting the unusual configuration, before
forcing full duplex with the instructions in
   http://www.scyld.com/network/eepro100.html

> alias eth0 eepro100
> options eepro100 0,0,0x30

  options eepro100 full_duplex=1
or
  options eepro100 options=0x30

> eepro100.c:v1.09j-t 9/29/99
> eepro100.c: $Revision: 1.20.2.3 $ 2000/03/02
> 
> 	The latest from ftp://scyld.com/pub/network/eepro100.c is:
> 
> eepro100.c:v1.10a 4/15/00
> 	Whick one should I use ? Kernel one or the latest one ? Or it doesnīt
> matter, both are good ??

I, of course, believe that my version is closer to correct.
"Fixed, and fixed again, and fixed again" means that the several people that
thought that had spotted bugs in my code didn't quite have it right either.

The good side of all of this is that you have another version to try if you
experience any problems.  Note that the problems are chip version specific,
so if you have a reliable installation, it will remain reliable until you
change the hardware.


Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Annapolis MD 21403