On Fri, Feb 16, 2001 at 09:18:34AM -0800, Jeremy C. Reed wrote:
> I have been requested to force my Intel Express Pro cards to be full
> duplex 100Mb.
> 
> Currently, the interface information says:
> 
> $ ifconfig -A fxp0
> fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>         media: Ethernet autoselect (100baseTX full-duplex)
>         status: active
>         inet 10.2.1.236 netmask 0xffff0000 broadcast 10.2.255.255
>         inet alias 10.2.3.26 netmask 0xff000000 broadcast 10.255.255.255
> 
> It is configured (/etc/ifconfig.fxp0) with:
> 10.2.1.236 netmask 0xffff0000 media autoselect
> 
> I was told Qwest's switch is standardized and the switch has auto
> negotiation set to off. I was also told that the switch and my NIC cards
> will not try to agree on a speed and the NIC has be forced to 100Mb full
> duplex or they will get a lot of errors on the switch.
> 
> I don't understand this autoselect -- can my interface change after it is
> configured? (It is now 100Mb full duplex; can it later become 10Mb or half
> duplex all by itself?)
> 
> What does this auto negotiation mean?

The board does an MII link partner autonegotiation with the remote end to find
the rigth mode.

> 
> I was told to try some mii-diag program (which they can provide code that
> they know works for Linux boxes). Do I need to hard code a NIC card?
> 
> Couldn't I just change it to:
> 10.2.1.236 netmask 0xffff0000 media 100baseTX mediaopt full-duplex

This would work too - as long as you're sure the switch doesn't do MII
autoneg. hardwiring mode will make the board stop anserwing MII
autoneg and the switch may fall back to half-duplex.

As long as it work in the mode it is I'd say to not change it :)

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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