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Re: half-/full-duplex ethernet and ifconfig

On Wed, Nov 14, 2012 at 09:45:25AM -0500, Thor Lancelot Simon wrote:
> However, to David's original question: if you're going to use the media
> and mediaopt settings to control speed/duplex, then yes, you get half-duplex
> unless you expressly specify "mediaopt full-duplex".  This was the original
> design (you can check with Jason) and drivers that do something else are
> nonconformant.  Changing it at this point will break things for many users,
> specifically by causing setups intended to be half-duplex to not be so.

I think that whether anything breaks for anyone depends on what changes
and how.  For example, I think it's safe to promote the media selection
'media 10baseT' somewhere in the kernel to 'media 10baseT mediaopt
half-duplex' and to use both IFM_HDX and IFM_FDX consistently inside the
kernel, especially when sending the current/active media *out* of the

That still doesn't give us a duplex "don't care" setting, but I cannot
think of a time when I *do* care what bitrate but I *don't* care what


David Young    Urbana, IL    (217) 721-9981

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