Date: Tue, 12 Oct 1999 14:05:53 -0400 From: Christopher Michaels <ChrisMic@clientlogic.com> To: 'Mitch Collinsworth' <mkc@Graphics.Cornell.EDU> Cc: 'Mike Squires' <mikes@sir-alan.chem.indiana.edu>, questions@FreeBSD.ORG Subject: RE: Setting Intel Pro100B to half duplex Message-ID: <6C37EE640B78D2118D2F00A0C90FCB4401105CE2@site2s1>
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Please re-read what was said. See below. > -----Original Message----- > From: Mitch Collinsworth [SMTP:mkc@Graphics.Cornell.EDU] > Sent: Tuesday, October 12, 1999 1:43 PM > To: Christopher Michaels > Cc: 'Mike Squires'; questions@FreeBSD.ORG > Subject: Re: Setting Intel Pro100B to half duplex > > > >Specify the 100BaseTX media w/o the "full-duplex" media option and it > will > >use half-duplex. Auto is notorious for not properly detecting things. > >-Chris > Read: set the media type (whereby disabling auto-neg), it will default to half-duplex. > umm, the last time this question came up (i.e. when I asked it), > the answer was that not specifying full-duplex puts you in autonegotiate > mode. > not if you specify a media type. 100baseTX is the media, full-duplex is a media option. > Ok, after double-checking myself on this, the answer you (Christopher > Michaels gave) was that you would get half-duplex. But the answer > David Greenman <dg@root.com> gave was: > > > The fxp device does default to auto-sense, but if you hard configure > the > >other end then [NWAY] autonegotiation is disabled, and thus whenever you > do > >that you have to set both ends if you want to be sure it is correct. The > >default without autonegotiation is half-duplex. > Read: disable auto-neg (by setting the media type), it will default to half-duplex. > meanwhile fxp(4) says: > > > The fxp device driver was written by David Greenman. > > Guess who I believe. > Both, because we both said the same thing? > Also I'm curious about your statement about autonegotiate being > notorious. I've heard this stated frequently but never with any data > to back it up. After the above reply from Mr. Greenman I read up on > autonegotiation in 3 different books on high-speed networking and have > come to the _tentative_ conclusion that this rumor is based on old > hardware. > > It seems that the 100 Mbps ethernet spec pre-dates the NWAY > autonegotation spec and in fact there was a different method used for > autonegotiation in the earliest days of 100 Mbps ethernet. My guess is > that this rumor was started during those early days and is still being > dutifully passed on by those who experienced problems with the early > non-NWAY equipment (and those who've heard the war stories from them). > > Can you (or anyone) state with any degree of certainty that any modern > equipment built with NWAY autonegotiation exhibits any problems with > autonegotiation? > I don't have definitive data to back that up. I have had auto-negotion set to full-duplex on a half-duplex hub (not switch). This coupled with the postings of many people on this list have led me to believe that the auto-neg is not quite right. > -Mitch To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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