Internet connection turning on and off continously (unstable internet connection)

[dm94]

Since last week, the internet connection is continuously switching on and off driving me crazy.  Many times a day (ca. 20-40 times) in every 10-15 minutes it turns off and after 2 minutes it switches back on again. (Berlin, 13347, Amsterdamer str.) For my work, I need a stable connection. It seems to me that the problem is really only started to happen in the last week. Is this something the provider knows about (such as known/planned work)? Did you get any other reports like this from the area or in general? Can I get some help to fix the problem?

[dm94]

I checked the status_event_log and 2 errors are always there:

1.) Black Address List Detected for Wifi

2.) DoS Attack UDP-Flooding for Firewall

please help me!

[dm94]

It is in literally every 10 minutes (see the attached image)

some more info to make it faster:

• Welchen Vertrag hast Du? Red Internet & Phone Young 100
  
• Welches Modem/ Router nutzt Du? TG3442DE.
  
• Nutzt Du ein Leih-Gerät von uns oder hast Du ein eigenes Gerät? Leih-Gerät
  
• Wie ist Dein Endgerät mit dem Modem verbunden? WLAN, 1 PC with cable 
  
• Welches Betriebssystem hast Du auf Deinem Rechner? Windows 10
  
• Beginn und Zeitraum der Störung ca 1 week ago

[Claudia]

Hello dm94,

do the problems happen with the PC that is connected through cable as well? Which firmware is on the router? Do you use something like Google Home, a Fire TV stick, Alexa or a similar device?

Kind regards,

Claudia

[dm94]

Dear Claudia,

thank you for the quick response. Here are the answers and some additional info.

Do you use something like Google Home, a Fire TV stick, Alexa or a similar device?

Yes I have a Beelink android TV box with Netflix.

Which firmware is on the router?

Firmware version: AR01.02.037.05_080119_711.PC20.10

Do the problems happen with the PC that is connected through cable as well?

The laptop is usually connected via WLAN, I only used LAN when I was checking the status logs.

There are 2 different (I think) problems I experience:

1. All WLAN connected devices are continously being diconnected (in every 2-5-10 mins) from the Wifi and then they reconnect again. This is (I think) different than what I wrote before because all the status LEDs are white during the reconnection. (This only affects the WLAN connected devices)
2. Many times during the day ( sometimes 20-30 times a day in the last week) there is a network outage causing the router to restart (phone and internet LEDs off, then  internet LED blinking red, then all comes back to white.). This affects all network connected devices irrespectively what kind of connection they use (LAN, WLAN).

Here is what I also tested (Wifi problems issue):

• To check if a different router could solve the 1.)  issue (with the wifi disconnect-reconnect) I used my older D-Link AC-1200 Router which I connected via LAN to the router from Vodafone.
• I then connected to the wifi of the D-Link router with all Wifi capable devices.
• There was no reconnection problem since then.
• This D-Link router doesn't use band-steering so the 2.4 and the 5 Ghz WLAN network is differentiated with different SSID.
• I still haven't checked if turning off the band-steering on the Vodafone router would solve the issue, do you think I should try it?

Here is what I also tested (Network outage issue):

• I still see the "DoS Attack UDP-Flooding" logs in my Vodafone router event log continously but sporaidically (not in every 10 minutes like a clockwork as before). Sometimes it is every five minutes then sometimes it doesn't happen for 1-2 hours.
• The last unexpected router restart (as mentioned before) happened yesterday in the evening around 10 pm.
• Since then there was no unexpected router restart but as again, the log is showing "DoS Attack UDP-Flooding"
• What do you think can cause these "DoS Attack UDP-Flooding" messages?

Please let me know what else can I check to solve the problem. I am currently using 2 Routers (so that at least the Wifi is stable) which is not very nice. Also this (presumably) will not solve the issue with the Vodafone router restarts.

Thank you again for your help,

Best,

David

[Claudia]

Hello dm94,

thank you for the additional information. I assume there may be two different problems, the one with the WiFi disconnects/ DoS Flooding is under investigation, but that shouldn't cause restarts. So I would like to check your access, please use the PM to send your address, customer number and date of birth. Leave a reply here which other devices you use and what firmware is on those devices.

Kind regards

Claudia

[dm94]

Dear Claudia,

I wanted to check the status log of the Vodafone Router again just now, and it seems to be disappeared from Status&Support. The Firmware version now on this router is AR01.01.117.01_091718_70.PC20.10.

Since last week when I connected the dlink router (to make the WLAN stable) and turned off the WLAN on the Vodafone router there was no unexpected shutdown and the wifi is stable as well. Or if there was I didn't notice it.

In the Vodafone router the uptime since last reboot is: 02 days, 08 hours and 03 minutes which looks good.

Without the logs I can not check if the Firewall messages are still coming or not.

Here are all the devices which are in the household with the Firmware/OS.

• Laptop Dell inspiron (dualboot Ubuntu 16 and WIN7) - the problem with the wifi is present with both OS
• Laptop Dell Latitude (Win10)
• Huawei P9 Plus phone: Android 7.0
• D-Link router: DIR-850L HW: B1 The firmware was 2.1 which is quite old so I updated it to 2.23
• BeeLink GT1 Android TV box: Android 7.1.2 

I send the personal info in DM as you requested.

Thank you for your help,

Best,

David

[Tobias]

Hey,

the connection looks completely clean, the line is up and does not break off like with the old firmware, if you only use one router after that, it might make sense to activate the bridge mode, then our device only functions as a modem

Regards

Tobias