coredns: bind to specific interfaces/IPs

ops/nixos/clouvider-fra01/default.nix

@@ -125,6 +125,7 @@ in {
     ];
   };
   my.ip.tailscale = "100.75.142.119";
+  my.coredns.bind = [ "enp1s0" "tailscale0" "127.0.0.1" "::1" ];
 
   # List packages installed in system profile. To search, run:
   # $ nix search wget

ops/nixos/clouvider-lon01/default.nix

@@ -133,6 +133,7 @@ in {
     };
   };
   my.ip.tailscale = "100.79.173.25";
+  my.coredns.bind = [ "br-ext" "tailscale0" "127.0.0.1" "::1" ];
 
   services.openssh.openFirewall = false;  # allowed by networking.firewall.extraCommands
   services.openssh.hostKeys = [

ops/nixos/frantech-las01/default.nix

@@ -65,6 +65,7 @@ in {
     };
   };
   my.ip.tailscale = "100.127.132.77";
+  my.coredns.bind = [ "ens3" "tailscale0" "127.0.0.1" "::1" ];
 
   system.stateVersion = "21.05";
 }

ops/nixos/frantech-lux01/default.nix

@@ -65,6 +65,7 @@ in {
     };
   };
   my.ip.tailscale = "100.125.159.57";
+  my.coredns.bind = [ "ens3" "tailscale0" "127.0.0.1" "::1" ];
 
   system.stateVersion = "21.05";
 }

ops/nixos/frantech-nyc01/default.nix

@@ -68,6 +68,7 @@ in {
     };
   };
   my.ip.tailscale = "100.99.236.25";
+  my.coredns.bind = [ "ens3" "tailscale0" "127.0.0.1" "::1" ];
 
   services.lukegbgp = let local = {
     asn = 205479;

ops/nixos/lib/coredns/default.nix

@@ -1,6 +1,11 @@
-{ depot, lib, ... }:
+{ depot, lib, config, ... }:
 
 {
+  options.my.coredns.bind = lib.mkOption {
+    type = lib.types.listOf lib.types.str;
+    default = [];
+  };
+
   config = {
     environment.etc."coredns-zones" = {
       source = "${./zones}";
@@ -38,7 +43,12 @@
           }
         '';
       in ''
+        (global) {
+          bind ${lib.concatStringsSep " " config.my.coredns.bind}
+        }
+
         . {
+          import global
           chaos
           log
           errors
@@ -52,6 +62,7 @@
         }
 
         (zonehdr) {
+          import global
           prometheus
           log
           errors