From 7a82b8085a08f725b0c1dabd32dbd64aeb8eb8cb Mon Sep 17 00:00:00 2001
From: Ryan Yin <xiaoyin_c@qq.com>
Date: Sun, 14 Sep 2025 10:40:12 +0800
Subject: [PATCH] fix: alert - add coredns, comment out some useless alert
 rules

---
 .gitignore                                    |  1 +
 .../alert_rules/coredns-exporter.yml          | 13 ++++++
 .../monitoring/alert_rules/node-exporter.yml  | 24 +++++------
 .../alert_rules/postgres-exporter.yml         | 42 +++++++++----------
 4 files changed, 47 insertions(+), 33 deletions(-)
 create mode 100644 hosts/idols-aquamarine/monitoring/alert_rules/coredns-exporter.yml

diff --git a/.gitignore b/.gitignore
index 5e9d423d..dc6ba733 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,3 +8,4 @@ logs/
 core*
 !core/
 !core.nix
+!coredns*
diff --git a/hosts/idols-aquamarine/monitoring/alert_rules/coredns-exporter.yml b/hosts/idols-aquamarine/monitoring/alert_rules/coredns-exporter.yml
new file mode 100644
index 00000000..0ca8b86d
--- /dev/null
+++ b/hosts/idols-aquamarine/monitoring/alert_rules/coredns-exporter.yml
@@ -0,0 +1,13 @@
+groups:
+  - name: CoreDNS Exporter
+
+    rules:
+      - alert: CorednsPanicCount
+        expr: "increase(coredns_panics_total[1m]) > 0"
+        for: 0m
+        labels:
+          severity: critical
+        annotations:
+          summary: CoreDNS Panic Count (instance {{ $labels.instance }})
+          description:
+            "Number of CoreDNS panics encountered\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"
diff --git a/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml b/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml
index 8ea26f8c..b28f4f4b 100644
--- a/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml
+++ b/hosts/idols-aquamarine/monitoring/alert_rules/node-exporter.yml
@@ -203,18 +203,18 @@ groups:
           summary: Host high CPU load (instance {{ $labels.instance }})
           description: "CPU load is > 80%\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"
 
-      - alert: HostCpuIsUnderutilized
-        expr:
-          '(100 - (rate(node_cpu_seconds_total{mode="idle"}[30m]) * 100) < 20) * on(instance)
-          group_left (nodename) node_uname_info{nodename=~".+"}'
-        for: 1w
-        labels:
-          severity: info
-        annotations:
-          summary: Host CPU is underutilized (instance {{ $labels.instance }})
-          description:
-            "CPU load is < 20% for 1 week. Consider reducing the number of CPUs.\n  VALUE = {{
-            $value }}\n  LABELS = {{ $labels }}"
+      # - alert: HostCpuIsUnderutilized
+      #   expr:
+      #     '(100 - (rate(node_cpu_seconds_total{mode="idle"}[30m]) * 100) < 20) * on(instance)
+      #     group_left (nodename) node_uname_info{nodename=~".+"}'
+      #   for: 1w
+      #   labels:
+      #     severity: info
+      #   annotations:
+      #     summary: Host CPU is underutilized (instance {{ $labels.instance }})
+      #     description:
+      #       "CPU load is < 20% for 1 week. Consider reducing the number of CPUs.\n  VALUE = {{
+      #       $value }}\n  LABELS = {{ $labels }}"
 
       - alert: HostCpuStealNoisyNeighbor
         expr:
diff --git a/hosts/idols-aquamarine/monitoring/alert_rules/postgres-exporter.yml b/hosts/idols-aquamarine/monitoring/alert_rules/postgres-exporter.yml
index 75d86a6b..9ea6ef5a 100644
--- a/hosts/idols-aquamarine/monitoring/alert_rules/postgres-exporter.yml
+++ b/hosts/idols-aquamarine/monitoring/alert_rules/postgres-exporter.yml
@@ -73,16 +73,16 @@ groups:
             "PostgreSQL instance has too many connections (> 80%).\n  VALUE = {{ $value }}\n  LABELS
             = {{ $labels }}"
 
-      - alert: PostgresqlNotEnoughConnections
-        expr: 'sum by (datname) (pg_stat_activity_count{datname!~"template.*|postgres"}) < 5'
-        for: 2m
-        labels:
-          severity: critical
-        annotations:
-          summary: Postgresql not enough connections (instance {{ $labels.instance }})
-          description:
-            "PostgreSQL instance should have more connections (> 5)\n  VALUE = {{ $value
-            }}\n  LABELS = {{ $labels }}"
+      # - alert: PostgresqlNotEnoughConnections
+      #   expr: 'sum by (datname) (pg_stat_activity_count{datname!~"template.*|postgres"}) < 5'
+      #   for: 2m
+      #   labels:
+      #     severity: critical
+      #   annotations:
+      #     summary: Postgresql not enough connections (instance {{ $labels.instance }})
+      #     description:
+      #       "PostgreSQL instance should have more connections (> 5)\n  VALUE = {{ $value
+      #       }}\n  LABELS = {{ $labels }}"
 
       - alert: PostgresqlDeadLocks
         expr: 'increase(pg_stat_database_deadlocks{datname!~"template.*|postgres"}[1m]) > 5'
@@ -109,17 +109,17 @@ groups:
             "Ratio of transactions being aborted compared to committed is > 2 %\n  VALUE = {{ $value
             }}\n  LABELS = {{ $labels }}"
 
-      - alert: PostgresqlCommitRateLow
-        expr:
-          'increase(pg_stat_database_xact_commit{datname!~"template.*|postgres",datid!="0"}[5m]) < 5'
-        for: 2m
-        labels:
-          severity: critical
-        annotations:
-          summary: Postgresql commit rate low (instance {{ $labels.instance }})
-          description:
-            "Postgresql seems to be processing very few transactions\n  VALUE = {{ $value
-            }}\n  LABELS = {{ $labels }}"
+      # - alert: PostgresqlCommitRateLow
+      #   expr:
+      #     'increase(pg_stat_database_xact_commit{datname!~"template.*|postgres",datid!="0"}[5m]) < 5'
+      #   for: 2m
+      #   labels:
+      #     severity: critical
+      #   annotations:
+      #     summary: Postgresql commit rate low (instance {{ $labels.instance }})
+      #     description:
+      #       "Postgresql seems to be processing very few transactions\n  VALUE = {{ $value
+      #       }}\n  LABELS = {{ $labels }}"
 
       - alert: PostgresqlLowXidConsumption
         expr: "rate(pg_txid_current[1m]) < 5"