This was one of those "Twilight Zone" things.. I had configured
a Linux box for a local reseller and had actually installed it at the
ultimate client's site a month back. It was "networked" only in
the sense that it had to talk to a network printer - it had no Internet
connection at all.
Of course I configured it with a private IP to match the subnet that
the printer was using, hooked it up and tested and all was good. All
was good until the store manager showed me an old wy60 terminal at
the front counter.. oops!
No serial ports in this puppy. That's typical today - everything
is USB. No big deal: you can buy USB to serial converters and you can still
buy PCI serial cards. I told my customer (the reseller) what he needed
Earlier this week I got a call from one of his regular employees who
had gone to the job to install a PCI serial card. He had something unhappy
to report: after installing the serial card, the network stopped working.
Of course I suggested pulling the card - he said that he had.. and that
the network was still not working. An "ifconfig" showed the correct
response, he had triple checked cables and everything else six ways from Sunday and the network was simply unresponsive. Ughh.
I know this tech - he's not a fool, so I knew he had in fact checked
everything he could. I asked him to bring me the machine for a look-see
and today he did.
My first observations matched his - nothing apparently wrong. But an "lspci -vv" revealed that things were not right..
I went right to Realtek and downloaded a new driver. That compiled and installed easily but nothing good happened. To my surprise, an "lsmod | grep r8"
showed that "r8169" was loaded and that r8168, although present in the modules
directory, was not.
I removed the r8169 files from the directory and rebooted, but r8168 did
not load. I did an "insmod" of it and the card popped right up working..
The heck with this: I don't what this is all about (I later found
a longish thread at RTL8102EL / Ubuntu 8.04 intermittent failure which describes
similar issues with a similar card) so I just jammed my insmod into
the top of the network startup script and that fixed it. Good enough
Inasmuch as I had the machine, I also installed the Lava PCI serial
card again and tested it and the network at the same time. All was
working, so I tore down the machine and will bring it back to them