Thanks, Hugo - I have read marked learnt and filed this. And yes, I was
heading off base very fast.
On Sunday 17 May 2009 20:12:27 Hugo Mills wrote:
> On Sun, May 17, 2009 at 07:59:23PM +0100, hantslug@??? wrote:
> > I have had this problem since yesterday evening.
>
> Why is it a problem? :)
Good question. I won't embarrass myself further by answering it. I thought I
sent an email to Paul thanking him and saying that I was an idiot - but it
doesn't seem to have got through.
So - thank you all very much. And I am an idiot. In the literal sense, of
course - but also in the modern derived sense. :-(
Lisi
I have left your excellent advice at the bottom in case someone looking to
trouble shoot a non-existent network problem somehow finds my reply, but for
some reason not your email.
[snip]
> You're heading way off base very fast, here...
>
> The first thing to do is to find out whether there actually is any
> network traffic going past. Then you need to find out whether it's
> network traffic that you want to be going through.
>
> Simple first test: if you bring down the main network interface on
> the machine, does the flickering stop?
>
> # ifdown eth0
>
> (Use ifup eth0 to bring it back up)
>
> If so, then it's probably not a hardware fault, and something
> really is sending network packets. Also try:
>
> # watch -n 1 ifconfig
>
> and watch the RX bytes and TX bytes counters.
>
> To investigate what might be doing this communication, netstat may
> help:
>
> # netstat -ap --inet --inet6
>
> Look at the tcp and tcp6 sockets that are "ESTABLISHED", and see
> what connections you've got. The last column will give you the pid of
> the process, in each case, which you can then look up in "ps axfww".
>
> If you still can't see what might be causing the communications
> you're worried about, then we can get all medieval on it with tcpdump
> and/or wireshark, but the above should be a good start.
>
> Hugo.