[tlug] Re: Networking problem

[Stephen Lee <sl@example.com>]

"Jean-Christian Imbeault" <jean_christian@example.com> wrote:
> 
> I'm having a bad networking day, again ...
> 
> The problem I am having is with "those people" that told me a class B hub 
> was causing my problems ;)

Is it possible to ask "those people" to bring two properly configured 
(according to them) laptops to your site, attach them directly to the
uplinks "they" provided, and check the speed?

This way, they can't blame your equipment.

> To remove the hubs as a source of problems I plugged one machine from each 
> subnet straight into the data center network but still saw the same problem.

It really sounds like an autonegotiation problem, or configuration
problem on "their" end.

I assume you have no access to the router on the far end, otherwise you
can check what the far end router thinks the line speed/duplex is.

What kind of network card do you have in your machines?  You should be
able to fix the speed/duplex via kernel/module options.

I'd suggest you try fixing a machine on the 'A' subnet to 100M/half
duplex, autonegotiation off and directly attaching it to the uplink,
then check if the speed changes.  Then try 100M/full, auto off.  If
neither talks at all then the far end might have been
misconfigured/misdetected as 10Mbps.

If 100M/half gets you good speed then again
misconfiguration/misdetection on the far end.

Stephen