diff --git a/nixops/rpi-server.nix b/nixops/rpi-server.nix
index 13ea3e1e..67b90846 100644
--- a/nixops/rpi-server.nix
+++ b/nixops/rpi-server.nix
@@ -128,7 +128,7 @@
   services.printing.enable = true;
   services.printing.drivers = [ pkgs.hplip ];
   services.printing.browsing = true;
-  services.printing.listenAddresses = [ "*:631" ];
+  services.printing.listenAddresses = [ "192.168.1.30:631" ];
   services.printing.defaultShared = true;
   hardware.sane.enable = true;
   hardware.sane.extraBackends = [ pkgs.hplip ];
@@ -140,7 +140,7 @@
   hardware.pulseaudio.tcp.anonymousClients.allowedIpRanges = ["192.168.1.0/24"];
 
   networking.firewall.allowedTCPPorts = [ 631 4713 ];
-  networking.firewall.allowedUDPPorts = [ 53 67 ];
+  networking.firewall.interfaces.wlan0.allowedUDPPorts = [ 53 67 ];
 
   nix.binaryCachePublicKeys = ["nixbld.m-labs.hk-1:5aSRVA5b320xbNvu30tqxVPXpld73bhtOeH6uAjRyHc="];
   nix.binaryCaches = ["https://cache.nixos.org" "https://nixbld.m-labs.hk"];