How to: The root route on which each incoming alert enters.
route:
  # The root route must not have any matchers as it is the entry point for
  # all alerts. It needs to have a receiver configured so alerts that do not
  # match any of the sub-routes are sent to someone.
  receiver: 'team-X-mails'

  # The labels by which incoming alerts are grouped together. For example,
  # multiple alerts coming in for cluster=A and alertname=LatencyHigh would
  # be batched into a single group.
  #
  # To aggregate by all possible labels use '...' as the sole label name.
  # This effectively disables aggregation entirely, passing through all
  # alerts as-is. This is unlikely to be what you want, unless you have
  # a very low alert volume or your upstream notification system performs
  # its own grouping. Example: group_by: [...]
  group_by: ['alertname', 'cluster']

  # When a new group of alerts is created by an incoming alert, wait at
  # least 'group_wait' to send the initial notification.
  # This way ensures that you get multiple alerts for the same group that start
  # firing shortly after another are batched together on the first
  # notification.
  group_wait: 30s

  # When the first notification was sent, wait 'group_interval' to send a batch
  # of new alerts that started firing for that group.
  group_interval: 5m

  # If an alert has successfully been sent, wait 'repeat_interval' to
  # resend them.
  repeat_interval: 3h

  # All the above attributes are inherited by all child routes and can
  # overwritten on each.

  # The child route trees.
  routes:
  # This route performs a regular expression match on alert labels to
  # catch alerts that are related to a list of services.
  - matchers:
    - service=~"^(foo1|foo2|baz)$"
    receiver: team-X-mails

    # The service has a sub-route for critical alerts, any alerts
    # that do not match, i.e. severity != critical, fall-back to the
    # parent node and are sent to 'team-X-mails'
    routes:
    - matchers:
      - severity="critical"
      receiver: team-X-pager

  - matchers:
    - service="files"
    receiver: team-Y-mails

    routes:
    - matchers:
      - severity="critical"
      receiver: team-Y-pager

  # This route handles all alerts coming from a database service. If there's
  # no team to handle it, it defaults to the DB team.
  - matchers:
    - service="database"

    receiver: team-DB-pager
    # Also group alerts by affected database.
    group_by: [alertname, cluster, database]

    routes:
    - matchers:
      - owner="team-X"
      receiver: team-X-pager

    - matchers:
      - owner="team-Y"
      receiver: team-Y-pager