[Soekris] Ethernet outages/autodetect weirdness on Net4801

[Stuart Henderson]

On 2008-04-19, Lars Noodén <lars at umich.edu> wrote:
> I have a Net4801-60 (256MB RAM) with OpenBSD 4.2 that sometimes gets no
> link with either cross-over or straight-through cables.
>
> Sometimes it's enough to simply switch to a different cable of the same
> type.  Other times, even though the cables are good (have used them with
> these and other devices) there is no link anyway.  Other times, the port
> will work with those cables but only when connected to a different device.
>
> I haven't changed the system configuration in months and the problem
> seems to have only appeared in the last weeks.
>
> The link status lights on the Ethernet ports are normally are green
> (100baseT), but individual ports (usually only 1-3 of the 5) will go to
> yellow (10baseT) and stay that way.  Or be off all together.
>
> What causes the ports to go offline completely?  ifconfig up/down
> doesn't change anything.  Though, sometimes switching from a cross-over
> to straight-through cable (or vice versa) fixes the problem.
>
> Are there situations in which the status must be forced?
>
> -Lars

There are autoneg problems with some devices (e.g. cat3550 which
advertises a media type it can't actually handle which causes a
problem when coupled with a bug present in quite a few OS), but 
AIUI in those cases it still does the same (though wrong) thing
each time.

Have you tried a different PSU yet? If you don't have one handy,
try removing devices (e.g. your 2-port card?) to lower the load
and see if that helps. Especially if you have the PSU type that
people have been reporting problems with on this list...