LinuxQuestions.org - Debian Buster and Raspbian apt update cannot resolve servers anymore since 1.5 months, very slow till no updates

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Debian Buster and Raspbian apt update cannot resolve servers anymore since 1.5 months, very slow till no updates

Hi!

since 1.5 months my internet connection makes problems and i changed a lot of things, .e.g. i changed my public IP to private in order to counteract DNS spoofing and DoS attacks. I changed from the Google DNS servers to my ISP servers DNS servers. Finally, i changed to a new internet fee from my provider from a 30MBit/10MBit LTE line to a 100MBit/20MBit LTE line. Things improved greatly but the only problem i have still is, that my apt update seems to not work anymore at all. Can it be that my ISPs DNS servers are spoiled in relation to Google DNS servers for resolving the linux apt servers? What else could be the reason for this problem?

What're your repo lists and what errors are thrown when

Code:

sudo apt-get update && sudo apt-get upgrade

Is envoked in terminal

My repo list buster lines

Code:

  Active apt repos in: /etc/apt/sources.list.d/debian-stable-updates.list 

  1: deb http://ftp.us.debian.org/debian/ buster-updates main contrib non-free

  Active apt repos in: /etc/apt/sources.list.d/debian.list 

  1: deb http://ftp.us.debian.org/debian/ buster main contrib non-free

  2: deb http://security.debian.org/ buster/updates main contrib non-free

Your problem description is extremely vague. How about showing commands, config files, error messages? You talk about changes at ISP level; have you changed anything on the computers that you try to update?

You mention problems resolving domain names. Have you tried public DNS servers like 1.1.1.1 or 8.8.8.8? Debian has repos in many places, in particular in places that have nothing to do with Debian. For example, a good update source for me is http://ftp.jaist.ac.jp/pub/Linux/debian (JAIST is a university and research institute in Japan). Do you have a problem resolving ftp.jaist.ac.jp? If not, change your sources.list accordingly. If you do, change the DNS server and try again.

Hi! For my RPi 4 4GB on Raspbian i used the predefined mirrors, which did not work anymore for me for some reason. It also said that the release files were not there anymore, but i think it was also because of DNS resolving issues. After a change to a different Raspbian mirror it worked again. For my Desktop i am using the same mirror like before which works now again and i don't know why. After turning back to a private IP, upgrading my internet tarif, buying a new mobile and buying a new router, removing all port forwards it seems like things are going back to normal operation mode. Maybe my ISPs DNS cache was spoofed and now finally is cleared and the private IP can now only be attacked by my ISP provider himself, which they never would do of course (for what reason should they destroy their own reputation/network integrity?).

Another problem that i identified is with pulseaudio. After recovering from sleep mode i have to always kill it in order to get normal playback on my desktop. It is so strange. The headphones always play nicely, but when i switch back to speakers surprisingly the playback speed is like 20x or something like that and also the volume is very loud. After killing pulseaudio things are normal again, but it could work nicely at first place without such spooky phenomena.