[Mail] Raise alert level for submission mail rejections

pica-metrologie/vmalert-rules.yml

@@ -201,11 +201,11 @@ groups:
       dashboard: '{{ if eq $labels.job "blackbox-http" -}}https://grafana.picasoft.net/d/8BOa8W47z/services-web?var-instance={{ $labels.instance }}{{- else if eq $labels.job "blackbox-dns" -}}https://grafana.picasoft.net/d/1twteMV7k/serveurs-dns?var-instance={{ $labels.instance }}{{- else if eq $labels.job "blackbox-mail" -}}https://grafana.picasoft.net/d/VB5CUrn7k/postfix{{- end -}}'
   - alert: PostfixRejection
     # As a test, alert when there is any rejection. If too much alert we will raise the threshold
-    expr: rate(postfix_smtpd_messages_rejected_total[5m]) > 0
+    expr: rate(postfix_smtpd_messages_rejected_total[5m]) > 1
     for: "1m"
     labels:
       severity: warning
     annotations:
       summary: Mail rejection
-      description: At least one mail sent from {{ $labels.instance }} have been rejected
+      description: People are trying to send rejected emails through {{ $labels.instance }} - probably spam
       dashboard: https://grafana.picasoft.net/d/VB5CUrn7k/postfix?var-instance={{ $labels.instance }}