Running Redhat and cablemodem - periodic drops that are recovered by restarting dhcpcd

I run RH9 and use Insight Cable Modem service. Cable light always stays
lit, but about every hour or less I will loose my Internet connection.
I will have a continuous ping running in the background and see when it
dies -- I kill off dhcpcd and restart it and then I regain my
connectivity...EVERY TIME.

Seems odd, huh?

Is there an explanation (and fix) for this, or has someone already written a
similar script that will kill and restart a service (in my case dhcpcd) when
2-3 consecutive packets are lost?

I have made an appointment for a cable guy to come out and look at my
"intermittent" problem, but I suspect it will be difficult to pinpoint.

Thanks,
Mike

On Fri, 03 Oct 2003 17:11:07 +0000, M Osborne wrote:

> I run RH9 and use Insight Cable Modem service. Cable light always stays
> lit, but about every hour or less I will loose my Internet connection. I
> will have a continuous ping running in the background and see when it
> dies -- I kill off dhcpcd and restart it and then I regain my
> connectivity...EVERY TIME.
>
> Seems odd, huh?
>
> Is there an explanation (and fix) for this, or has someone already
> written a similar script that will kill and restart a service (in my
> case dhcpcd) when 2-3 consecutive packets are lost?
>
> I have made an appointment for a cable guy to come out and look at my
> "intermittent" problem, but I suspect it will be difficult to pinpoint.
>
> Thanks,
> Mike

What do your logs say?


--
-- James Fenimore Cooper
The tendency of democracies is, in all things, to mediocrity, since the tastes,
knowledge, and principles of the majority form the tribunal of appeal.

>>>>> "M" == M Osborne <M> writes:
M>
M> I run RH9 and use Insight Cable Modem service. Cable light always
M> stays lit, but about every hour or less I will loose my Internet
M> connection. I will have a continuous ping running in the
M> background and see when it dies -- I kill off dhcpcd and restart it
M> and then I regain my connectivity...EVERY TIME.
M>
M> Seems odd, huh?
M>
M> Is there an explanation (and fix) for this, or has someone already
M> written a similar script that will kill and restart a service (in
M> my case dhcpcd) when 2-3 consecutive packets are lost?
M>
M> I have made an appointment for a cable guy to come out and look at
M> my "intermittent" problem, but I suspect it will be difficult to
M> pinpoint.
M>
M> Thanks,
M> Mike

I have seen behaviour similar to this when using a flaky ethernet
card. You might try swapping out for another one if you have one.

But sometimes it seems to be the cable modem itself.

On one Road Runner connected machine I have, I put the following in a
file /etc/nettest.sh :

#!/bin/bash
ping 24.93.40.62 -c 1 > /dev/null;
if [ $? -ne 0 ]
then
/etc/init.d/networking stop
sleep 2
/etc/init.d/networking start
fi
exit 0

and then I cron jobbed it to run every ten minutes. Note that the IP
in question is my ISP's domain name server; choose an appropriate one
for you, I choose the domain name server because I figured if it
wasn't down but the network was up there was little harm in turning
the network on and off, as I likely wasn't getting work done anyway.

--Rob