diff --git a/parsons/mail.nix b/parsons/mail.nix
index f03af06..1645885 100644
--- a/parsons/mail.nix
+++ b/parsons/mail.nix
@@ -1,4 +1,4 @@
-{ config, pkgs, lib, sources, ... }:
+{ config, options, pkgs, lib, sources, ... }:
 
 {
   imports = [ sources.nixos-mailserver.outPath ];
@@ -20,6 +20,14 @@
     monitoring = {
       enable = true;
       alertAddress = "admin@hacc.space";
+      config = (lib.replaceStrings ["port 22"] ["port ${toString (lib.head config.services.openssh.ports)}"] options.mailserver.monitoring.config.default) + ''
+        check host onlyoffice with address onlyoffice.infra4future.de
+              if failed
+                 port 443
+                 protocol https
+                 status = 302
+              then alert
+      '';
     };
     domains = [
       "hacc.space"