Re: [PLUG] Puzzling networking problem

["Mark M. Hoffman" <mhoffman@lightlink.com>]

* Mark Dominus <mjd-lists-plug@plover.com> [2003-12-11 14:03:59 -0500]:
> 
> I have a recurring network problem.  Packets addressed to one or
> another of my static addresses will just stop arriving.
> 
> I believe the problem isn't on my side.  This is because I can run ping
> on a remote network, sending packets to one of my working addresses,
> and the effect is obvious: the 'activity' lamp on my DSL modem blinks
> every second, whenever the ping packets come in.   The periodic
> blinking starts when I run the ping and stops when I stop the ping, so
> it's clear that the ping packets are arriving at the modem.

I use DCAnet.  I've also seen routing snafus... but only twice in 1.5
years, and once was after I moved and was trying to get reconnected.
Neither outage was more than 1/2 day.  

I keep a spare baby hub between my Linux router and the DSL modem - this
makes it easy to plug in a 2nd machine as a packet sniffer using Ethereal.
Note that for this purpose, it has to be a hub, not a switch.  So, I
think it was helpful for me to be able to say to the DCAnet tech:
"I see your ping (from w.x.y.z) and I see my response to it... I see
my DHCP request but I don't see a response from your side..." etc.

> When I run the same 'ping' command to send packets to a non-working
> address, the lamp does not blink in this was.  I think this shows that
> the packets are not making it to my DSL modem at all.  I think that
> this rules out anmy configuration problem on my local network or my
> hosts.

Ethereal is probably more reliable for this.

<cut>
> DCANet has not been helpful.  The technical support manager I have
<cut>

I was going to mention that DCAnet is in some ways hamstrung by 
Verizon whose service they resell; but Andy explained it better
than I could have anyway.  What he didn't say but I will...

If you're annoyed enough to switch providers, at least don't switch
*to* Verizon; you'll only be downgrading your service and potentially
encouraging Verizon to muck it up for their resellers.

> I am really mystified here, and it seems that DCANet and I are getting
> into a noncommunicative mode.  They will not answer my questions and
> they take a long time to return my calls.  I'm afraid that they have
> tagged me as a troublesome customer.  From my end, it looks like there
> is a problem in the network that is not my fault and they won't help
> me track it down.
>
> Has anyone had any similar sort of technical problem?  Does anyone
> have any advice for dealing with a service provider that seems to
> think that I am the problem here, and that the only way to deal with
> me is to ignore me?

The trick to getting good support from any helpdesk is to prove to them
that you know what you're talking about.  It's a bit of a chicken and
egg problem though... if you know what you're talking about you usually
have little reason to call in the first place.

And have some empathy: the poor techs have to deal with clueless Windows
users all day. ;) You couldn't pay me enough...

One thing I really like about DCAnet is that their front-line techs
even *know* what a packet sniffer *is*.  Try getting that from Verizon,
PacBell, TWC, or any other huge provider.

Regards,

-- 
Mark M. Hoffman
mhoffman@lightlink.com

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