awesome-prometheus-alerts/dist/rules/mongodb/percona-mongodb-exporter.yml

groups:

- name: PerconaMongodbExporter

  rules:

    - alert: MongodbDown
      expr: 'mongodb_up == 0'
      for: 0m
      labels:
        severity: critical
      annotations:
        summary: MongoDB Down (instance {{ $labels.instance }})
        description: "MongoDB instance is down\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

    - alert: MongodbReplicationLag
      expr: 'mongodb_mongod_replset_member_optime_date{state="PRIMARY"} - ON (set) mongodb_mongod_replset_member_optime_date{state="SECONDARY"} > 10'
      for: 0m
      labels:
        severity: critical
      annotations:
        summary: MongoDB replication lag (instance {{ $labels.instance }})
        description: "Mongodb replication lag is more than 10s\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

    - alert: MongodbReplicationHeadroom
      expr: '(avg(mongodb_mongod_replset_oplog_head_timestamp - mongodb_mongod_replset_oplog_tail_timestamp) - (avg(mongodb_mongod_replset_member_optime_date{state="PRIMARY"}) - avg(mongodb_mongod_replset_member_optime_date{state="SECONDARY"}))) <= 0'
      for: 0m
      labels:
        severity: critical
      annotations:
        summary: MongoDB replication headroom (instance {{ $labels.instance }})
        description: "MongoDB replication headroom is <= 0\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

    - alert: MongodbNumberCursorsOpen
      expr: 'mongodb_mongod_metrics_cursor_open{state="total"} > 10 * 1000'
      for: 2m
      labels:
        severity: warning
      annotations:
        summary: MongoDB number cursors open (instance {{ $labels.instance }})
        description: "Too many cursors opened by MongoDB for clients (> 10k)\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

    - alert: MongodbCursorsTimeouts
      expr: 'increase(mongodb_mongod_metrics_cursor_timed_out_total[1m]) > 100'
      for: 2m
      labels:
        severity: warning
      annotations:
        summary: MongoDB cursors timeouts (instance {{ $labels.instance }})
        description: "Too many cursors are timing out\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

    - alert: MongodbTooManyConnections
      expr: 'avg by(instance) (rate(mongodb_connections{state="current"}[1m])) / avg by(instance) (sum (mongodb_connections) by (instance)) * 100 > 80'
      for: 2m
      labels:
        severity: warning
      annotations:
        summary: MongoDB too many connections (instance {{ $labels.instance }})
        description: "Too many connections (> 80%)\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

    - alert: MongodbVirtualMemoryUsage
      expr: '(sum(mongodb_memory{type="virtual"}) BY (instance) / sum(mongodb_memory{type="mapped"}) BY (instance)) > 3'
      for: 2m
      labels:
        severity: warning
      annotations:
        summary: MongoDB virtual memory usage (instance {{ $labels.instance }})
        description: "High memory usage\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"