Grab the latest live Ubuntu live DVD or CD. See if *that* can talk to
the ethernet port, since the kernels tend to be more recent than the
industry grade, stable kernels in Scientific Linux. But "after a power
failure on a clear day" sounds like hardware failure.. I assume you;ve
tested the cables and upstream network ports?

If the chipset is toast, which can happen, a decent PCI/E or even old
PCI network card should support GigE quite easily. If you need network
alive while testing kernels, USB network devices can be quite handy.

On Fri, Mar 7, 2014 at 4:47 PM, Larry Linder
<[log in to unmask]> wrote:
> I am looking for a way to check the functionality of an Ethernet port on a 4
> mo old new system.   We use this box for number crunching and reducing data.
> Since no one uses the desktop we left it as "Gnome" and set up network.  This
> also the same box we found the SL 6.x had a broken driver for the chip set.
> Thanks to some serious help we were able to download the driver for the
> Ethernet chip set and it worked for a long time.
>
> After a power failure on a clear day we noticed that it would boot and run but
> no intranet.   The power failure was city wide for about 5 sec.  Just enough
> to turn on the UPS,s and EM Lights.
>
> I have look on the net and there is a lot of people offering suggestions but
> nothing you can hang you hat on.  Most just reference a lot of applications.
>
> Tried:
> drop down's for "preferences" and network set up.  restart "network" &
> NetworkManagement" .  These look OK.
>
> Apps:
> "ifconfig"
> etho:  says that it read a large number of packets and transmitted none.
>
> "ss"
> gives a lot of information but Its pretty criptic to say the least.
>
> The Ethernet chip set is on the mother board and I hate to dismantel it
> replace the mother board and have the same problem.  I was looking for a way
> to test it with a loop back scheme and monitor the transmission with a scope.
> The Ethernet chip set supports 10/100/1000 megHz.   Because of the size of the
> data sets we need the 1 g. rate.   We plan to upgrade our entire network to 1
> G router, and switches once this problem is resolved.
> Only change one thing at a time.
>
> Larry Linder