From 12e55b9a956bcbed90ce4f925ef56e9e1812eda0 Mon Sep 17 00:00:00 2001
From: Tom Hughes <tom@compton.nu>
Date: Tue, 19 Jul 2022 00:47:00 +0100
Subject: [PATCH 1/1] Add an alert for unusually low apache request rates

---
 cookbooks/prometheus/templates/default/alert_rules.yml.erb | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/cookbooks/prometheus/templates/default/alert_rules.yml.erb b/cookbooks/prometheus/templates/default/alert_rules.yml.erb
index b928520ed..4b5a0c60f 100644
--- a/cookbooks/prometheus/templates/default/alert_rules.yml.erb
+++ b/cookbooks/prometheus/templates/default/alert_rules.yml.erb
@@ -52,6 +52,13 @@ groups:
           alertgroup: "{{ $labels.instance }}"
         annotations:
           busy_workers: "{{ $value | humanizePercentage }}"
+      - alert: apache low request rate
+        expr: rate(apache_accesses_total[$__rate_interval]) / rate(apache_accesses_total[$__rate_interval] offset 1w) < 0.25 and rate(apache_accesses_total[1h] offset 1w) > 2
+        for: 15m
+        labels:
+          alertgroup: "{{ $labels.instance }}"
+        annotations:
+          request_rate: "{{ $value | humanizePercentage }}"
   - name: chef
     rules:
       - alert: chef client not running
-- 
2.39.5