# other rules to consider:
# filesystem, network, ntp rules:
# https://github.com/cloudalchemy/ansible-prometheus defaults/main.yml
# on my system, the interpolated values are in /a/opt/ansible-prometheus/rules.yml
#


groups:
- name: standard
  rules:
  - alert: mailtest-check
    expr: |-
      time() - mailtest_check_last_usec > 60 * 12
    labels:
      severity: day
    annotations:
      description: '{{ $labels.instance }} mailtest-check'
      summary: '{{ $labels.instance }} mailtest-check'

  # 42 mins: enough for a 30 min queue run plus 12
  - alert: mailtest-check
    expr: |-
      time() - mailtest_check_last_usec > 60 * 42
    labels:
      severity: prod
    annotations:
      description: '{{ $labels.instance }} mailtest-check'
      summary: '{{ $labels.instance }} mailtest-check'

  - alert: 1pmtest
    expr: hour() == 18 and minute() < 5
    for: 0m
    labels:
      severity: daytest
    annotations:
      summary: Prometheus daily test alert (instance {{ $labels.instance }})
      description: "Prometheus daily test alert if no other alerts. It
    is an end to end test.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"


# https://awesome-prometheus-alerts.grep.to/rules


# todo, we should probably group the prometheus alerts that indicate a
# host-local problem.
# eg, set a label  alert-group: local-prom, then make a receiver that
# groups by it when the alert-group is local-prom.

- name: awesome prometheus alerts
  rules:

  - alert: PrometheusJobMissing
    expr: absent(up{job="prometheus"})
    for: 30m
    labels:
      severity: day
    annotations:
      summary: Prometheus job missing (instance {{ $labels.instance }})
      description: "A Prometheus job has disappeared\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTargetMissing
    expr: up == 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus target missing (instance {{ $labels.instance }})
      description: "A Prometheus target has disappeared. An exporter might be crashed.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

      # todo: this should supress the above alert
  # - alert: PrometheusAllTargetsMissing
  #   expr: count by (job) (up) == 0
  #   for: 30m
  #   labels:
  #     severity: day
  #     alert-group: local-prom
  #   annotations:
  #     summary: Prometheus all targets missing (instance {{ $labels.instance }})
  #     description: "A Prometheus job does not have living target anymore.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusConfigurationReloadFailure
    expr: prometheus_config_last_reload_successful != 1
    for: 30m
    labels:
      severity: day
    annotations:
      summary: Prometheus configuration reload failure (instance {{ $labels.instance }})
      description: "Prometheus configuration reload error\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

      # I have an out of band alert to make sure prometheus is up. this
      # looks like it would generate false positives. todo: think
      # through what a valid crash loop detection would look like.
  # - alert: PrometheusTooManyRestarts
  #   expr: changes(process_start_time_seconds{job=~"prometheus|pushgateway|alertmanager"}[15m]) > 10
  #   for: 0m
  #   labels:
  #     severity: warning
  #   annotations:
  #     summary: Prometheus too many restarts (instance {{ $labels.instance }})
  #     description: "Prometheus has restarted more than twice in the last 15 minutes. It might be crashlooping.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusAlertmanagerJobMissing
    expr: absent(up{job="alertmanager"})
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus AlertManager job missing (instance {{ $labels.instance }})
      description: "A Prometheus AlertManager job has disappeared\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusAlertmanagerConfigurationReloadFailure
    expr: alertmanager_config_last_reload_successful != 1
    for: 30m
    labels:
      severity: day
    annotations:
      summary: Prometheus AlertManager configuration reload failure (instance {{ $labels.instance }})
      description: "AlertManager configuration reload error\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusNotConnectedToAlertmanager
    expr: prometheus_notifications_alertmanagers_discovered < 1
    for: 30m
    labels:
      severity: day
    annotations:
      summary: Prometheus not connected to alertmanager (instance {{ $labels.instance }})
      description: "Prometheus cannot connect the alertmanager\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusRuleEvaluationFailures
    expr: increase(prometheus_rule_evaluation_failures_total[3m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus rule evaluation failures (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} rule evaluation failures, leading to potentially ignored alerts.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTemplateTextExpansionFailures
    expr: increase(prometheus_template_text_expansion_failures_total[3m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus template text expansion failures (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} template text expansion failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusRuleEvaluationSlow
    expr: prometheus_rule_group_last_duration_seconds > prometheus_rule_group_interval_seconds
    for: 5m
    labels:
      severity: warn
    annotations:
      summary: Prometheus rule evaluation slow (instance {{ $labels.instance }})
      description: "Prometheus rule evaluation took more time than the scheduled interval. It indicates a slower storage backend access or too complex query.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusNotificationsBacklog
    expr: min_over_time(prometheus_notifications_queue_length[30m]) > 0
    for: 0m
    labels:
      severity: warn
    annotations:
      summary: Prometheus notifications backlog (instance {{ $labels.instance }})
      description: "The Prometheus notification queue has not been empty for 10 minutes\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusAlertmanagerNotificationFailing
    expr: rate(alertmanager_notifications_failed_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus AlertManager notification failing (instance {{ $labels.instance }})
      description: "Alertmanager is failing sending notifications\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  # file_sd doesnt count as service discovery, so 0 is expected.
  # - alert: PrometheusTargetEmpty
  #   expr: prometheus_sd_discovered_targets == 0
  #   for: 30m
  #   labels:
  #     severity: day
  #   annotations:
  #     summary: Prometheus target empty (instance {{ $labels.instance }})
  #     description: "Prometheus has no target in service discovery\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTargetScrapingSlow
    expr: prometheus_target_interval_length_seconds{quantile="0.9"} > 90
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus target scraping slow (instance {{ $labels.instance }})
      description: "Prometheus is scraping exporters slowly\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusLargeScrape
    expr: increase(prometheus_target_scrapes_exceeded_sample_limit_total[10m]) > 10
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus large scrape (instance {{ $labels.instance }})
      description: "Prometheus has many scrapes that exceed the sample limit\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTargetScrapeDuplicate
    expr: increase(prometheus_target_scrapes_sample_duplicate_timestamp_total[5m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus target scrape duplicate (instance {{ $labels.instance }})
      description: "Prometheus has many samples rejected due to duplicate timestamps but different values\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbCheckpointCreationFailures
    expr: increase(prometheus_tsdb_checkpoint_creations_failed_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB checkpoint creation failures (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} checkpoint creation failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbCheckpointDeletionFailures
    expr: increase(prometheus_tsdb_checkpoint_deletions_failed_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB checkpoint deletion failures (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} checkpoint deletion failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbCompactionsFailed
    expr: increase(prometheus_tsdb_compactions_failed_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB compactions failed (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} TSDB compactions failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbHeadTruncationsFailed
    expr: increase(prometheus_tsdb_head_truncations_failed_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB head truncations failed (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} TSDB head truncation failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbReloadFailures
    expr: increase(prometheus_tsdb_reloads_failures_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB reload failures (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} TSDB reload failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbWalCorruptions
    expr: increase(prometheus_tsdb_wal_corruptions_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB WAL corruptions (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} TSDB WAL corruptions\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"

  - alert: PrometheusTsdbWalTruncationsFailed
    expr: increase(prometheus_tsdb_wal_truncations_failed_total[1m]) > 0
    for: 30m
    labels:
      severity: warn
    annotations:
      summary: Prometheus TSDB WAL truncations failed (instance {{ $labels.instance }})
      description: "Prometheus encountered {{ $value }} TSDB WAL truncation failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}"