My son has set the house up with a Pi-Hole
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At first it was a for a few minutes at a time, then a few hours at a time, then overnight.
I quit trying to use it and the problems went away.
My theory is that I tripped some fraud detection software run by the advertisers, who would know their traffic was disappearing, who in turn notified comcast that my IP address was violating terms of service. All done by software, I doubt any human intervention took place. Not that they care that little old me doesn't see their ads, it's more bad actors trying to steal clicks or impressions or identifying information etc. Very hard to know the details unless you are a network engineer, it's not the kind of thing they want the public or the black hats to know.
But I'm sure it happened because I had the lowest tier comcast and a docsis 3.1 modem on fairly new cable plant. It was very solid. I could repeatably get my cable disabled just by turning on the pi-hole and waiting less than 15 minutes.
But I searched online and everyone else seems to be able to use them, so maybe it is me.
Networks are very funny things and much more complicated than most appreciate. Almost 10 years ago a blog post[0] I wrote with some crazy network debugging was the top post on HN.
I don’t expect you to read the full post but I was able to root cause analysis an issue with cause and effect that no one with network experience would think possible. Long story short in my case a specific byte value at an exact byte location would crash the ethernet controller and cause it to drop off the PCIe bus. You could forward billions of packets and it would never happen. Or one wrong one and end up having to power cycle to get it back…
I’m guessing you have a similar situation here. Maybe the Raspbery PI is glitching somehow and spamming absolute garbage traffic at the modem, which may or may not be forwarded to the DOCSIS side (which is shared broadcast). I could see Comcast booting the modem from the network in this scenario.
Maybe you have your own “packet of death” type scenario where the DNS requests from the Pi Hole and some other specific aspect of the traffic trigger something in the modem (more likely) or head end and crashing (kind of like my situation).
Or any of the other millions of things with a technical underlying cause that could be presenting here.
Unless you want to spend hundreds of hours debugging this like I did you’ll have to do what we all do everyday which is shrug your shoulders, say “Huh, that was weird”, and accept that you found yet another strange bug out there.
What I can say is what we’ve all said and what you’ve found elsewhere. This is not some Comcast advertising related conspiracy targeting you.
Hanlon’s Razor and all.
[0] - http://blog.krisk.org/2013/02/packets-of-death.html?m=1
My theory is that I tripped some fraud detection software run by the advertisers, who would know their traffic was disappearing, who in turn notified comcast that my IP address was violating terms of service. All done by software, I doubt any human intervention took place. Not that they care that little old me doesn't see their ads, it's more bad actors trying to steal clicks or impressions or identifying information etc. Very hard to know the details unless you are a network engineer, it's not the kind of thing they want the public or the black hats to know.
But I'm sure it happened because I had the lowest tier comcast and a docsis 3.1 modem on fairly new cable plant. It was very solid. I could repeatably get my cable disabled just by turning on the pi-hole and waiting less than 15 minutes.
But I searched online and everyone else seems to be able to use them, so maybe it is me.
Only problem is my Pi died and I haven't set up a new one, been considering setting up a Pi cluster so if one goes down I don't have to scramble to fix it for Internet to work in our house (although I can just update the DNS at my router until it's fixed, so not too bad).
You don't need a raspberry pi to do dns filtering.
Now that I think about it… doesn't this in combination with IoT and planned obsolescence pretty much guarantee that block lists will have to grow in an unbounded fashion over time?
I wonder when the first "Legacy IoT Telemetry 2010-2020" list (or something similar) will pop up :)
That is, if it doesn't exist already.
It made me rip out what few smart devices I owned and blocked all social media sites.
I have to say installation on Ubuntu Server (which I run on a Pi4 just fine) couldn't be easier as it is as simple as 'sudo snap install adguard-home' and it all just works. Very nice.
In the browser uBlock Origin handles this fine. On device you need to use a third party app to view YouTube that has adblocking functionality built in.
Used to have it running as a USB Gadget off the router's USB port but that had some weird issues that the Ethernet Power Adapter just bypasses.
My phones are always rooted though, I want all the control I can get for my device.