mass-check has been killing my internet connection - buggy cablemodem

[Da...@chaosreigns.com]

I previously said Comcast seemed to be killing my connection regularly
around when I had mass-check scheduled to upload.

Last weekend, when rebooting my cablemodem wasn't fixing my connection
anymore, I called them, and they told me I had "an End Of Life modem".
Meaning that for some reason, they no longer support it, and I need to
take it in and get a replacement.  They never notified me.

I figured regularly killing my internet connection was their very poorly
chosen way of getting me to replace my unsupported modem.

(My next scheduling opportunity to replace the modem was today.)

This morning it didn't happen.  mass-check ran, my logs rsynced up, and I
still had a working internet connection.

But I noticed a change I made didn't work (adding darxus-trap), so I
ran mass-check again.

And my internet connection died.

Comcast wasn't triggering my internet connection to die.  mass-check was.
Probably with all the network tests.

I'm not saying there's anything at all wrong with mass-check.  Just that
on Comcast's network, with certain old unsupported cablemodems, mass-check
can trigger problems with the modem or the modem's relationship to the
network, killing the internet connection.

-- 
"...pain is a fundamental human experience..."
- http://www.stumptuous.com/cms/displayarticle.php?aid=115
http://www.ChaosReigns.com

Re: mass-check has been killing my internet connection - buggy cablemodem

["Warren Togami Jr." <wt...@gmail.com>]

On 3/12/2011 8:32 AM, Kevin A. McGrail wrote:
> I would argue you are possibly triggering a DoS response from Comcast.
>
> What DNS servers are you using? When your internet dies, does your cable
> modem believe it still has a link?
>

My thought exactly, this is most likely Comcast thinking you are 
infected because this is highly unusual traffic.

I'd advise trying to run your own DNS server, do not use their DNS 
server.  But they might be intercepting DNS traffic and this might not 
help.  You may need some kind of VPN to use DNS without interference.

Warren

Re: mass-check has been killing my internet connection - buggy cablemodem

["Kevin A. McGrail" <KM...@PCCC.com>]

I would argue you are possibly triggering a DoS response from Comcast.

What DNS servers are you using? When your internet dies, does your cable modem believe it still has a link?

Can you ping something by IP?

Mass check can't trigger a modem disconnecting any more than any other program. But you could have faulty equipment or a traffic pattern that is causing an issue. Something akin to the traffic shaping some ISPs have been accused of doing for example with P2P and VOIP services.
Regards,
KAM

Darxus@chaosreigns.com wrote:

I previously said Comcast seemed to be killing my connection regularly around when I had mass-check scheduled to upload. Last weekend, when rebooting my cablemodem wasn't fixing my connection anymore, I called them, and they told me I had "an End Of Life modem". Meaning that for some reason, they no longer support it, and I need to take it in and get a replacement. They never notified me. I figured regularly killing my internet connection was their very poorly chosen way of getting me to replace my unsupported modem. (My next scheduling opportunity to replace the modem was today.) This morning it didn't happen. mass-check ran, my logs rsynced up, and I still had a working internet connection. But I noticed a change I made didn't work (adding darxus-trap), so I ran mass-check again. And my internet connection died. Comcast wasn't triggering my internet connection to die. mass-check was. Probably with all the network tests. I'm not saying there's anything at all wrong with mas!
 s-check.
Just that on Comcast's network, with certain old unsupported cablemodems, mass-check can trigger problems with the modem or the modem's relationship to the network, killing the internet connection. -- "...pain is a fundamental human experience..." - http://www.stumptuous.com/cms/displayarticle.php?aid=115 http://www.ChaosReigns.com 

Re: [SA-dev] mass-check has been killing my internet connection - buggy cablemodem

[Adam Katz <an...@khopis.com>]

On 03/12/2011 08:11 AM, Darxus@chaosreigns.com wrote:
> I'm not saying there's anything at all wrong with mass-check.  Just
> that on Comcast's network, with certain old unsupported cablemodems,
> mass-check can trigger problems with the modem or the modem's
> relationship to the network, killing the internet connection.

Tell them what you're doing.  Comcast sponsored the MIT Spam Conference
several times in the last few years; they might be willing to give you
an exception to their attack filters.

I also agree with Warren; try to host your own DNS, maybe get the rsync
updates for local mirrors of the DNSBLs that facilitate that.