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Re: [LUG] Network hubs



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Pete Walker wrote:
> Neil Williams wrote:
>
>>
> Yes. AFAIK,  the cable from hub1 to hub2 should go into hub
2's uplink
> (if it has one). Not sure what you mean by uplink button

Most older ethernet hubs have an uplink button, I think mostly
took the role of a crossover cable.

Quite a lot also used 10B2 as an option for uplink - if the
uplink is in a cabinet or secured computer room this was a good
choice as you were less likely to pull the wrong cable, and some
gave you an extra port this way.

> as the hubs I
> have used just have 2 sockets for port 8, one with a crossover for
> uplink. New hubs have some sort of autodetect which means they
can work
> out if it is uplink or a normal connection.

My worse ethernet hub experience was a network in France which
didn't have Ethernet keepalive - it took ages to get a SUN
networking guru who could tell me what the mysterious flashing
diagnostics meant, and where to set the ignore keepalive flag.

The sins of others we've seen with Ethernet hubs, spanning trees
and the like would make your hair curl.

There was a report of a hospital discussed before that deployed
Ethernet with too many hubs between end points, broke the
spanning tree algorithmn, and caused all sorts of weird
problems, can't remember if it was here or NANOG. It was
portrayed as a brilliant technical success for those that fixed
it, but looked to me like basic ethernet misconfiguration, we
fixed worse all the time without comment or press releases, and
definitely without spending 6 figure sums with large equipment
vendors.
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