Weird networking issue.

Stephen J. Wilcox steve at telecomplete.co.uk
Wed Jan 8 00:30:45 UTC 2003


> > I think we all agree that autonegotiation is evil, and should be avoided
> > whenever possible.  When you are looking for the root cause of the errors on
> 
> I don't agree. I have seen more problems generated by incompetence in 
> trying to fix duplex/speed, than I have seen problems generated by autoneg 
> not working properly.
> 
> I am always amazed by the fact that very few people out there know that 
> you have to lock duplex at BOTH ENDS of any given link for it to work 
> properly.

So thats human error not a problem with using forced settings, eliminate the
human error and I think you'll see forced always works, autoneg sometimes
works. (For future reference dont employ incompetent people to run your networks
folks!)

> Generally, in a LAN environment with good quality switches and good
> network cards, autoneg works just fine. Yes, with 10/100 meg
> fiber/converters converters you should definately lock duplex, but in most
> other cases I recommend to leave the duplex setting to auto.

Heh. I dont want to look at examples or find out what your experience is but in
mine across a wide range of vendors its prone to problems.

> Yes, cisco routers are notoriously bad at doing autoneg, but I blame that
> on cisco and not on autoneg. The el cheapo $50 desktop switches seem to
> hack autoneg just fine.

Have you looked at what autoneg is.. its horrible, a hack to help out the above
incompetent engineers who dont know how to force duplex. 

.. well thats my opinion on the matter anyhow :)

Steve




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