No DNS resolving on Debian after installed resolvconf

[Paderman]

I have a VPS and if resolvconf, is installed, no DNS (address) will be resolving and I don't knows how can I fix it. I must reinstall the system. Ping, apt and many more doesn't work with addresses but with IP it works.

I removed entries with resolvconf and after running the script, resolving is possible.

I don't know why problem is present.

[Techwizz-somboo]

I'm experiencing the same thing on both Debian and Ubuntu 20.04 LTS server it seems

[Paderman]

I'm experiencing the same thing on both Debian and Ubuntu 20.04 LTS server it seems

OK, you have the same problem 😢🫣

[hdn012]

I encountered the same issue while using a VPS with Debian 12. I followed these manuals (https://wiki.debian.org/resolv.conf, https://manpages.debian.org/bookworm/resolvconf/resolvconf.8.en.html) and it appears to help me solve the problem.

Option 1:

When resolveconf was installed, it copied the old /etc/resolv.conf to /etc/resolvconf/resolv.conf.d/original so the manual suggests

Note also that the administrator can choose to create a symbolic link in /etc/resolvconf/resolv.conf.d/ from tail to original so that the contents of original are always added to the end of the dynamically generated file.

Option 2:

Edit /etc/network/interfaces and add dns-nameserver entries in the appropriate stanza for example. Mine is as follow:

Details

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
        address xxx
        netmask xxx
        broadcast xxx
        network xxx
        gateway  xxx
        # BELOW ENTRIES WERE ADDED
        dns-nameserver 1.1.1.1
        dns-nameserver 1.0.0.1

auto eth0:1
iface eth0:1 inet static
        address xxx
        netmask xxx
iface eth0:1 inet6 static
        address xxx
        netmask xxx
        gateway  xxx

auto eth0:2
iface eth0:2 inet static
        address xxx
        netmask xxx
iface eth0:2 inet6 static
        address xxx
        netmask xxx

auto eth0:3
iface eth0:3 inet static
        address xxx
        netmask xxx
iface eth0:3 inet6 static
        address xxx
        netmask xxx

then sudo ifup -a, then reboot for safe measure.

[Techwizz-somboo]

I usually just make my resolv.conf immutable which also works well. (After making it a real file instead of a symlink)

[mewostick]

My ridiculous solution is to make a script that sets the name servers on boot with systemd. While this works for me on Debian 12 ARM64 it may break other setups further since I rely on cloud-init.

/root/fix-dns.sh

#!/bin/bash
echo nameserver 9.9.9.9 > /etc/resolv.conf

/etc/systemd/system/fix-dns.service

[Unit]
Description=Run fix-dns.sh on boot

[Service]
ExecStart=/root/fix-dns.sh
Type=oneshot
RemainAfterExit=yes
User=root

[Install]
WantedBy=multi-user.target

execute in the terminal "sudo systemctl enable fix-dns && sudo systemctl start fix-dns"