2 KNE100TX cards, no hub/switch, options= ?

Eric Jorgensen alhaz@xmission.com
Fri Apr 28 19:38:56 2000


> > 	Example: Cisco Catalyst switches and 3Com SuperStack II switches, when
> > network utilization is fairly high (over 30%), fail to autonegotiate to
> > full duplex. This caused me several hours of BS just this week. 
> 
> Sigh.  Those switches are broken.  It is sad that the two largest names in
> the industry both produced broken hardware a few years ago.  And I don't
> mean "broken" in the gentle sense of making non-optimal technical
> decisions.  They just flat out had a flawed hardware design.  They tried to
> cover up by spreading the FUD that autonegotiation was bad and that
> everyone should force the speed and duplex, even while their smaller
> competitors (almost everyone else in the industry) had perfectly working
> implementations.
> 
> Their current products do work with autonegotiation.

	Actually the catalyst switches I'm refering to are, to say the
least, very current. They negotiate fine with nics, not with some other
switches (the problems we had were all cisco-3com switch-switch 
interaction - and the problem doesn't occur when the traffic level is low)

	But I know what you mean, the right way is the cisco way, eh?
Even if they change their mind. 
 
> > then later admitted that the only way their unit will negotiate to full
> > duplex is if the device the AP100 is attached to is already in full
> > duplex mode when it connects - ie, has been forced to full duplex. 
> 
> Ehhh?  If you force 100baseTx or full duplex, you *cannot* do
> autonegotiation.  The closest you can get is to advertise only full duplex
> media types.  I think they were feeding you a line..

	Actually what they said was that it doesn't autonegotiate. And
they even eventually explained what happens -- 

"When the AP reboots, we come up briefly at 100meg half duplex, before the
config file is loaded. When the config file loads, it hits the ethernet
config record and sets it to full. By this time, the Catalyst has probably
already switched to 100 half."

	So this would leave one to believe that unless you disable
autonegotiation on the other end of the connection, it will only come up
100 hdx. Indeed, when i asked them to verify this, they responded saying
"Well, obviously!"

	Xedia makes some excellent products - I have only the highest
regard for them in that respect. They do, however, have one or two little
problems. That and the way the AP100 is sorta memory starved and they
don't offer a way to upgrade it without voiding the warranty, even tho it
takes 72 pin simms. BGP4 support is pretty useless in 8 megs of ram,
depending on what you want to do with it.  

	 They've been consumed by the ring of fire, tho, so it probably
doesn't matter anymore. 

> > 	If it doesn't work with a crossover cable, it might be a bogus cable,
> > try a different cable. You might have bogus nics, too. 
> 
> "It can't be mispaired, I made it myself."
> Cat5 pairing is *not* intuitively obvious.  Most people should not be making
> their own cables.

	And not all RJ45's are created equal. And "Ideal" crimpers are
less than ideal. I hear ya . . . 


 - Eric
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