After pgrading to 23.11 Adguard Home will not start and I can't change the Nameservers on the box

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1

I have a Nixos server that among other things runs Adguard Home, just DNS, no DHCP. I also have it setup with it nameservers being 127.0.0.1. Below is what I think are the relevant part of the config:

  # Enable networking.
  networking.hostName = "auir";
  networking.nameservers = [ "127.0.0.1" ];


 # Enable Adguard Home and set bassic settigns
  services.adguardhome = {
    enable = true;
    settings = {
      bind_host = "127.0.0.1";
      bind_port = 3000;
      dns = {
        bind_hosts = [ "127.0.0.1" "192.168.50.20" ];
        upstream_dns = [ "64.59.135.135" "64.59.128.112" ];
        all_servers = true;
        bootstrap_dns = [ "64.59.135.135" "64.59.128.112" ];
        rewrites = [
          {
            domain = "*.mydomain.com";
            answer = "192.168.50.20";
          }
          {
            domain = "mydomain.com";
            answer = "192.168.50.20";
          }
       ];
      };
    };
  };

I am in the process of upgrade it from 23.05 to 23.11 and running into some issues. I used the following step to take the upgrade:

sudo nix-channel --add https://channels.nixos.org/nixos-23.11 nixos
sudo nixos-rebuild boot --upgrade
sudo shutdown -r now

Everything seem to work correctly, however after the upgrade Adguard Home will not start:

sudo systemctl status adguardhome.service
● adguardhome.service - AdGuard Home: Network-level blocker
     Loaded: loaded (/etc/systemd/system/adguardhome.service; enabled; preset: enabled)
     Active: activating (auto-restart) (Result: exit-code) since Thu 2023-11-30 15:31:38 MST; 2s ago
    Process: 110266 ExecStartPre=/nix/store/fw97wkhd53cl2phgw5h27qc0i3yj92ss-unit-script-adguardhome-pre-start/bin/adguardhome-pre-start (code=exited, status=0/SUCCESS)
    Process: 110270 ExecStart=/nix/store/idf1g0533i94jwzy6k0l7d85fkz6j61s-adguardhome-0.107.36/bin/adguardhome --no-check-update --pidfile /run/AdGuardHome/AdGuardHome.pid --work-dir /var/lib/AdGuardHome/ --config /var/lib/AdGuardHome/AdGuardHome.yaml (code=exited, stat>
   Main PID: 110270 (code=exited, status=1/FAILURE)
         IP: 0B in, 0B out
        CPU: 92ms

Nov 30 15:31:38 auir systemd[1]: adguardhome.service: Main process exited, code=exited, status=1/FAILURE
Nov 30 15:31:38 auir systemd[1]: adguardhome.service: Failed with result 'exit-code'.
Nov 30 15:31:38 auir systemd[1]: adguardhome.service: Triggering OnFailure= dependencies.

I am not sure why it will not start, but one thing that is limiting my troubleshooting, I now don’t have DNS on this machine. I have tried changing my /etc/nixos/configuration.nix to uses a different nameserver, but when I do a sudo nixos-rebuild switch I get Couldn’t resolve host name errors.

How would I change my nameserver in the live system, so I can get sudo nixos-rebuild switch to work? Also, if anyone has any idea why Adguard Home is not working, please share.

Thank you

2

It has taken me some time to get back to this, but I think I got it solved.

First, I edited /etc/resolv.conf changing the nameserver to something different (1.1.1.1) and then restart network-interfaces.target. This got DNS working, and I was able to do a sudo nixos-rebuild --upgrade switch with an updated configuration.nix that specified a different nameserver.

As for why Adguard Home was not after the upgrade, I am not sure what the issue was. I was able to get it working again by:

  1. Disabling AdGuard in my config (services.adguardhome.enable = false),
  2. Doing an sudo nixos-rebuild --upgrade switch,
  3. Deleting the AdGuard files (sudo rm -r /var/lib/private/AdGuardHome),
  4. Enabling AdGuard in my config (services.adguardhome.enable = true),
  5. Doing an sudo nixos-rebuild --upgrade switch.

Cheers