inventory.yml

all:
  children:
    # docker_nodes is the parent group for docker_build_hosts and docker_swarm_nodes
    docker_nodes:
      children:
        # defines which host will perform the build
        # only the first host in this group will ever be used
        docker_build_hosts:
          hosts:
            # for these examples we'll build images on the same host ansible is running on
            # but we give it a made up name, which doesn't matter as we override connection
            docker-build:
              ansible_host: localhost
              ansible_connection: local
        docker_swarm_nodes:
          children:
            # swarm managers are a subset of swarm nodes that are defined as managers of the node
            # however it is valid, and potentially preferred, for all swarm nodes to be managers
            docker_swarm_managers:
              hosts:
                # for these examples we'll deploy images on the same host ansible is running on
                # but we give it a made up name, which doesn't matter as we override connection
                docker-swarm01:
                  ansible_hostname: localhost
                  ansible_connection: local


    # because we plan on deploying all of our images that we've built, docker_services is a group that contains
    # docker_build_images
    docker_services:
      children:
        docker_build_images:

          # each image we want to build is defined as a host, and thus can make use of ansible's variable precedence
          hosts:

            # don't do much other than run splunk
            hello_swarm_forwarder:
              # every image definition must have a version
              version: 1.0.0

            # enable healthcheck for the _internal index
            internal_healthcheck_forwarder:
              # remember every image must have a version number
              version: 1.0.0

              # in splunk's metrics.log
              # for the per_index_thruput group
              healthcheck_metrics_group: per_index_thruput
              # for the _internal series
              healthcheck_metrics_series: _internal
              # expect to see non-zero thruput no older than 60 seconds
              healthcheck_allowed_age_seconds: 6

            # enable healthcheck for the _internal and _audit indexes
            internal_introspection_healthchecks_forwarder:
              version: 1.0.0

              metrics_healthchecks:
                - group: per_index_thruput
                  series: _internal
                  # 6 seconds will show how this check is sometimes stale, then recovers
                  allowed_age_seconds: 6
                - group: per_index_thruput
                  series: _introspection
                  # 60 seconds should always show this check as fresh
                  allowed_age_seconds: 60

            # bind mount
            volumes_mounted_forwarder:
              version: 1.0.0

              host_volumes:
                # create a bind mount to see how the container can be made aware of specific host data
                - mount_type: service_bind
                  source: /etc/hosts
                  target: "{{ splunk_home }}/host_etc_hosts"

                # create a persistent volume for $SPLUNK_HOME/var
                # note that if your swarm nodes don't have a common storage path, this likely needs to be NFS
                # or it's only persistent per node, and not across all nodes
                - mount_type: service_volume
                  name: volumes_mounted_forwarder_service_volume
                  path: "{{ splunk_home }}/var"