DNS Not Working After Upgrade to Bullseye

Troubleshooting
1

Creating a bug report/issue

I have searched the existing open and closed issues

Required Information

  • DietPi version | cat /boot/dietpi/.version
    G_DIETPI_VERSION_CORE=8
    G_DIETPI_VERSION_SUB=25
    G_DIETPI_VERSION_RC=2
    G_GITBRANCH=‘8’
    G_GITOWNER=‘MichaIng’

  • Distro version | echo $G_DISTRO_NAME $G_RASPBIAN
    bullseye 1

  • Kernel version | uname --all
    Linux PiHole 5.10.103-v7+ #1529 SMP Tue Mar 8 12:21:37 GMT 2022 armv7l GNU/Linux

  • Architecture | dpkg --print-architecture
    armhf

  • SBC model | echo $G_HW_MODEL_NAME or (EG: RPi3)
    Rpi 3 Model B+ (arnv7l)

  • SD card used | (EG: SanDisk ultra)
    SanDisk

Additional Information (if applicable)

  • Software title | PiHole / DietPi
  • Was the software title installed freshly or updated/migrated? Yes
  • Can this issue be replicated on a fresh installation of DietPi? Probably Not.

I just upgraded to Bullseye, but now I am unable to resolve hosts on my Pihole machine. My laptop is still working on the WiFi using PiHole as DNS though.

When I run host or nslookup I just get the following:
;; connection timed out; no servers could be reached

2

Did you follow all steps from our upgrade guide?

Based on the kernel version, apt full-upgrade was probably missing, and maybe some reinstalls.

The Pi-hole host itself does not use Pi-hole for its DNS resolution, does it? Do you use a static IP or DHCP with an IP reservation at the router/DHCP server? To check which nameserver(s) it currently uses:

cat /etc/resolv.conf