diff --git a/nixops/desktop.nix b/nixops/desktop.nix
index 77a9e0f..875343c 100644
--- a/nixops/desktop.nix
+++ b/nixops/desktop.nix
@@ -26,6 +26,7 @@ in
 
   networking.hostName = host;
   networking.firewall.allowedTCPPorts = [ 1883 ];
+  networking.firewall.allowedUDPPorts = [ 1883 ];
 
   time.timeZone = "Asia/Hong_Kong";