[K12OSN] Excessive collisions cripple network -- Suggestions for solutions?

[Julius Szelagiewicz]

On Wed, 30 Apr 2008, Tom Wolfe wrote:

> Our Linux labs continue to work great. However, our network has now become
> much bigger, with lots of little satellite switches in our mini labs
> (classes that are serviced by a single Cat 5e wire now have 5-15 K12LTSP
> clients via simple switches).
>
> Every couple of months it seems that accidentally ?someone? plugs both
> ends of an ethernet cable into the same switch. This ends up sending out
> collisions like nuts and slows or cripples our network. I then have to
> figure out where the problem is and fix it.
>
> Are there any recommendations out there on how to prevent these problems
> from affecting my whole network, e.g. is there a switch that will shut
> down a port if it's generating too many collisions or problems? And maybe
> even email me to alert me of the problem??
>
> Suggestions would be appreciated!
>
Many optipons, all good options cost money. The simplest if not least
expensive is to use switches that support spanning tree protocol, end
enable it. There is a small packet delay penalty, but it is usually
negligible. All my HP Procurve switches have STP set and have no problem
with looped cabling. since this happens in rooms served by a single cat5
wire, local STP is really crucial. If only a big upstream switch has this
capability, it will stop all traffic from the affected room.
julius