diff --git a/scripts/update.sh b/scripts/update.sh
index e2e176d..116307e 100644
--- a/scripts/update.sh
+++ b/scripts/update.sh
@@ -340,6 +340,22 @@ JAILEOF
       echo "[✓] Fail2Ban Jails installiert (dovecot, postfix, nginx)."
     fi
   fi
+
+  # Postfix: Hostname in mydestination eintragen damit System-Mails (cron, PHP)
+  # nicht als Relay-Versuch gewertet werden und fail2ban die eigene IP nicht bannt
+  if command -v postconf >/dev/null 2>&1; then
+    local srv_host
+    srv_host=$(hostname -f 2>/dev/null || hostname 2>/dev/null || true)
+    if [[ -n "$srv_host" ]]; then
+      local current_dest
+      current_dest=$(postconf -h mydestination 2>/dev/null || true)
+      if ! echo "$current_dest" | grep -qF "$srv_host"; then
+        postconf -e "mydestination = $srv_host, localhost.localdomain, localhost"
+        postfix reload >/dev/null 2>&1 || true
+        echo "[✓] Postfix: $srv_host zu mydestination hinzugefügt (System-Mails lokal zugestellt)."
+      fi
+    fi
+  fi
 }
 
 # -------- Guards --------------------------------------------------------------