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Every day at the same time, my internet dies for 1 minute. How do I investigate?

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Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#21
Does your WiFi provide a way to monitor the real time bandwidth usage of each device? I was experiencing randomly timed outages for a while. Turned out to be our various phones and other devices randomly saturating my low upload bandwidth with cloud backups. That shouldn’t kill my downstream bandwidth, but it does.

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#22
post #19
post #9

Launch ´mtr google.com’ on one of your devices (preferably connected via Ethernet to your router) a few minutes before the cut off, and watch what happens when the cut occurs. It will show you exactly which equipment on the route starts dropping. Although I suspect your ISP has a 24h lease and your modem renegociates at 3:40 everyday

So then the trick is to forgo internet by disconnecting power from a few minutes before that time to the middle of the night and get power back? I do feel for the ISP's with this setup because the right thing to do would be to write in the installation manual: "Only install in the deep of night".

Well they could 1) renew the IP before it expires or 2) reboot the modem remotely at 3:30am for example.

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#23
@OP did you try calling support to report the problem? It's almost impossible to diagnose ANY internet problems (not related to your own equipment of course) and the ISP has tools and access to do it. In any case, it's much easier and faster to contact support.

In my experience, even if I discover what is the problem, if it's on their side I still have to go through support to get it fixed, so I just wasted my time. And in most cases the lowest level of support doesn't even write down the information I give in the ticket, even if I send an email.

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#24

Does your WiFi provide a way to monitor the real time bandwidth usage of each device? I was experiencing randomly timed outages for a while. Turned out to be our various phones and other devices randomly saturating my low upload bandwidth with cloud backups. That shouldn’t kill my downstream bandwidth, but it does.

It doesn't kill your downstream directly, but you can't send the acknowledgements for the download fast enough if the upload is saturated. That kills your download speed

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#26
Some german ISPs used to force a reset of home internet connections every 24h to trigger IP changes so that static IPs would remain reserved for the business tier. The time of the reset could be shifted by preemptively reconnecting at a desired time, they only reset the link after 24h of actual uptime.

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#28
Make sure all your network devices / computers are synced via NTP, or at least accurate to the second.

Hardwire the Pi to the network. Start a verbose traceroute and ping loop on a device on WiFi, as well as the Pi. Once it fails, observe the lights on your router/wifi device(s). Note time to the second of the start and finish of the outage, and the behavior of the lights. Check the results of your traceroutes/pings. Start digging through the logs of each network device.

Also, you can never quite rule out power, even if the lights stay on. A power conditioning UPS is useful here.

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#29
It was easy way of dealing with router hanging up due to accumulated problems used by amateur internet providers. Just disconnect it from power once a day.

You can do that with cheap socket timer.

Not sure why would anyone set it to the middle of the day. Maybe error in setting times or clock or it was set intentionally so that you can service it at normal hours if it doesn't come back on.

The problem is you can put in 'off' time and 'on' time but they have to be at least 1 minute apart.

Re: Every day at the same time, my internet dies for 1 minute. How do I investigate?

#30

Did you check if your public IP changes after this minute? I don't know if this still happens but back in the past my router did this every 24h to get a new IP.

A lot of service providers do this because they do not want you to host static services from your "dynamic" home IP, as they are selling "business" lines with dedicated static IPs. Or at least they used to do this for that reason. By now it's just some thing a lot of ISP do. I have seen other possible explanations like ISP claiming this is a "security" feature because attackers cannot have permanent access without always learning the new IP, which is supposedly somehow hard. This is pretty bull tho. If attackers have access to your system they could just run software signalling them back any IP changes. And even nmapping the entire IP space of an ISP to find a service you were hitting again is very feasible.

Anyway, if the ISP does this, then you have to reconnect once every day (or sometimes every two days), and if you don't do so manually they will just cut your connection on their side and make you reconnect.

My (German) ISP does that too, the one I had before did it, the one before did it as well.

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