[PLUG] Network issues

[Denis Heidtmann]

On Mon, Jan 25, 2010 at 12:33 PM, Steve D... <blitters at gmail.com> wrote:
> On Sat, Jan 23, 2010 at 7:17 PM, Denis Heidtmann
> <denis.heidtmann at gmail.com> wrote:
>>
>> Thanks for all the information.  You have saved me from a fruitless
>> bunch of tests.  I do not claim to have gotten my head around all the
>> stuff in those links, but I have the impression that if the NIC is
>> misbehaving during the autonegotiation process I have no reasonable
>> way to find that out.
>
>  Not without a digital storage scope and maybe a PCI(e) bus debugger. :-)
>
>> The connection has not had a failure for some days now (many shutdowns
>> and reboots, but no interruption of power to the modem or the
>> computer), even though renegotiation is likely happening often.  Also,
>> when failure occurs the only thing which appears to fix it is to shut
>> down and power down the computer.  I conclude from this that most
>> likely the NIC occasionally gets into a bad state during power-up.
>
>  Things are much more complex than they appear.  Motherboards have
> brains now.  The state of the ethernet negotiation isn't tied to the
> front panel power button and the ifconfig command any longer.  Newer
> motherboards have advanced power and management features like "Green
> PC", ACPI, and IPMI.  These motherboards have systems running beneath
> your level that have their own agenda.  Your ability to interact with
> these systems is limited.
>
>  You really don't control the motherboard any longer.  A
> micro-controller called a Management Engine (ME) controls the system
> power and PCI/PCIe bus.  The MEs have a tendency to do their own
> thing.  They will down speed and/or renegotiate the link whenever
> their programming says to.  It ain't easy being a Green PC.
>
>  The ME actually talks directly to the NIC.  The PCIe 2.1 standard
> (and above) include a serial link from the ME into the PCIe cards.
> The older standards used an external serial cable.  The ME *controls*
> your NIC.  It can do all kinds of interesting things, like IPMI and
> LOM.  The *only* way for a user to determine the state of the NIC is
> to monitor the LEDs.
>
>  You may be able to turn off most of the ME by fiddling with the BIOS
> and turning off ACPI support in the kernel.  You can tell if ACPI is
> running by trying to put the OS into Sleep (S3) or Hibernate (S4).
> You OS cannot go to S3/S4 unless ACPI and the ME is enabled  Turning
> off ME (not really... psyc!) may cut down on some of the link problems
> you're seeing.  It will also disable many of the "Green PC" features
> of your system.
>
>> Do you see this as an accurate assessment?
>
> Pretty much...  Your available choices are:
>
> 1) Deal with it... You many have to "ifconfig up" your eth port from
> time to time. :-)
>
> 2) Nail your NIC and switch port to 1000-Full.  This will only works
> on a managed switch.  Only nailing one side can result in a
> duplex-mismatch.
>
> 3) Install a different NIC.  I like the Intel cards.  Make sure to
> replace the distro's in-box driver.  The latest and greatest Intel
> Linux drivers up on Sourceforge are pretty good.
>
> 4) Open up an issue with your NIC manufacture.  They may be willing to
> troubleshoot the problem and provide a fixed driver.  This would be
> good for the Linux community.  Somebody has to be willing to feel the
> pain so we can all reap the benefits. :-)
>
> Steve D...
>
Once again I thank you for the information.  I have been thinking that
the thing which changes from one power-on--boot to the next is the
time from when the juice is connected to the desktop to when I press
the front panel button.  The stuff about the ME may fit in with this.
I can explore this when I feel not having a connection will not be too
painful.

With regard to your steps above.  1) I have tried ifdown/ifup to no
avail.  I have not tried ifconfig up.  When I break the network I will
try it.  2) my modem does not support 1000, and I have no switch. 3) A
new card is on my list.  4) I plan to do that, but the thought of
dealing with ASUS (the MB mfg.) makes me think of a tar pit.

Thanks.

-Denis