AlertManager Config

global:
  resolve_timeout: 5m
  smtp_smarthost: 'smtp.example.com:587'
  smtp_from: 'alertmanager@example.com'
  smtp_auth_username: 'alertmanager@example.com'
  smtp_auth_password: 'changeme'

templates:
  - '/etc/alertmanager/templates/*.tmpl'

route:
  group_by: ['alertname', 'cluster', 'service']
  group_wait: 30s
  group_interval: 5m
  repeat_interval: 4h
  receiver: 'slack-default'

  routes:
    # Critical alerts → PagerDuty
    - match:
        severity: critical
      receiver: pagerduty
      continue: true

    # Warnings → Slack
    - match:
        severity: warning
      receiver: slack-default

receivers:
  - name: 'slack-default'
    slack_configs:
      - api_url: 'https://hooks.slack.com/services/CHANGE/ME'
        channel: '#alerts'
        send_resolved: true
        title: '{{ template "slack.title" . }}'
        text: '{{ template "slack.text" . }}'

  - name: 'pagerduty'
    pagerduty_configs:
      - service_key: 'YOUR_PAGERDUTY_SERVICE_KEY'
        send_resolved: true

inhibit_rules:
  # Suppress warning if critical is already firing for the same alertname+instance
  - source_match:
      severity: 'critical'
    target_match:
      severity: 'warning'
    equal: ['alertname', 'instance']