From 2c11b87fdbe29a79fd4836ceebf83ff3d3538d58 Mon Sep 17 00:00:00 2001
From: jenkins <jenkins@bstein.dev>
Date: Wed, 5 Aug 2026 21:33:11 -0300
Subject: [PATCH] fix(monitoring): Alertmanager must HELO with a FQDN for Mailu

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 services/monitoring/helmrelease.yaml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/services/monitoring/helmrelease.yaml b/services/monitoring/helmrelease.yaml
index 21b5ca75a..eb0337c58 100644
--- a/services/monitoring/helmrelease.yaml
+++ b/services/monitoring/helmrelease.yaml
@@ -754,6 +754,9 @@ spec:
         smtp_smarthost: mailu-front.mailu-mailserver.svc.cluster.local:25
         smtp_from: alertmanager@bstein.dev
         smtp_require_tls: false
+        # Mailu rejects the default "HELO localhost" with 504 5.5.2; the
+        # greeting has to be a fully-qualified name.
+        smtp_hello: alerts.bstein.dev
       route:
         receiver: default
         group_wait: 30s