diff --git a/machines/genepi/monitoring/default.nix b/machines/genepi/monitoring/default.nix
index 3cd9c37..e5a3e88 100644
--- a/machines/genepi/monitoring/default.nix
+++ b/machines/genepi/monitoring/default.nix
@@ -2,4 +2,8 @@
   imports = [
     ./grafana.nix
   ];
+
+  networking.firewall.interfaces."zts7mq7onf".allowedTCPPorts = [
+    9090 # prometheus web interface
+  ];
 }