[H-GEN] Problem

[Robert Brockway]

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On Fri, 18 Oct 2002, Stephen Brine wrote:

> Hi all, I am trying to track down what is broken.
> Occasionally I get a problem where my connection is still up but nothing
> get through. This doesn't happen all the time but when it does and I ping
> (in this case a machine that is on the other side (on the network of the
> other side) I get what is below. Now I am not sure exactly what the problem
> is or where it lies (whether it is my machine or whether it is the modem).
> A drop of the connection and a redial solves the problem but I don't like
> doing this, sometimes it happens immediately after a dial in other times it
> happens after a day or longer (if I am lucky) Most of the time the

At this point I was thinking of classic line noise.  The modem "freezes"
as it retrains or as ppp despirately tries to get requests for resends
through.

The physical line quality could be poor.  Line tests rarely help as the
big Telcos set only very low standards for data connections (saves them
having to dig up the street for all those poor people whos 56k modems
won't go over 28k :)

> The machine is a Pent 133, 32Meg running Mandrake 7.2 (as it has done for
> the last year and a bit) running as a ip masq between a 56k Modem and my
> network. What else would you want to know.

Who is your ISP?

> One thing I didn't do is keep a log of ip's (dynamic) that I have had when
> the problem occurs.

If the ISP has multiple boxes you connect to when dialing, it is possible
it is related to one of them.

> Results of ping

[Interesting ping results deleted]

If it were a line problem I don't feel your pings should get corrupted.  A
fault line would result in a resend at the PPP level, which would result
in either poor performance across the link (latency) or dropped packets
depending on how bad the link was.

Could your ISP be mangling packets upstream (say, at a firewall).
Have you talked to your isp about this?

Other info to help us...

What is your kernel version?

Has the box been patched at any point?

Was there ever a time with your current setup that the problem _did not_
occur.  If so, what did you change.  Think carefully on this one.  Any
sysadmin is full of stories where people claimed to make to change but
when you pin it down they remember something that did change afterall.
If you think it is a minor point, mention it anyway - too much info is
better than too little.

Cheers,
	-Rob

-- Robert Brockway B.Sc. email: robert at timetraveller.org  ICQ: 104781119
   Linux counter project ID #16440 (http://counter.li.org)
   "The earth is but one country and mankind its citizens" -Baha'u'llah


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