using-entrypoint-features.md

Using entrypoint features

Warning

This documentation covers the legacy mode of ARC (resources in the actions.summerwind.net namespace). If you're looking for documentation on the newer autoscaling runner scale sets, it is available in GitHub Docs. To understand why these resources are considered legacy (and the benefits of using the newer autoscaling runner scale sets), read this discussion (#2775).

Runner Entrypoint Features

Environment variable values must all be strings

The entrypoint script is aware of a few environment variables for configuring features:

apiVersion: actions.summerwind.dev/v1alpha1
kind: RunnerDeployment
metadata:
  name: example-runnerdeployment
spec:
  template:
    spec:
      env:
        # Disable various runner entrypoint log levels 
        - name: LOG_DEBUG_DISABLED
          value: "true"
        - name: LOG_NOTICE_DISABLED
          value: "true"
        - name: LOG_WARNING_DISABLED
          value: "true"
        - name: LOG_ERROR_DISABLED
          value: "true"
        - name: LOG_SUCCESS_DISABLED
          value: "true"
        # Issues a sleep command at the start of the entrypoint
        - name: STARTUP_DELAY_IN_SECONDS
          value: "2"
        # Specify the duration to wait for the docker daemon to be available
        # The default duration of 120 seconds is sometimes too short
        # to reliably wait for the docker daemon to start
        # See https://github.com/actions/actions-runner-controller/issues/1804
        - name: WAIT_FOR_DOCKER_SECONDS
          value: 120
        # Disables the wait for the docker daemon to be available check
        - name: DISABLE_WAIT_FOR_DOCKER
          value: "true"
        # Disables automatic runner updates
        # WARNING : Upon a new version of the actions/runner software being released 
        # GitHub stops allocating jobs to runners on the previous version of the
        # actions/runner software after 30 days.
        - name: DISABLE_RUNNER_UPDATE
          value: "true"

There are a few advanced envvars also that are available only for dind runners:

apiVersion: actions.summerwind.dev/v1alpha1
kind: RunnerDeployment
metadata:
  name: example-runnerdeployment
spec:
  template:
    spec:
      dockerdWithinRunnerContainer: true
      image: summerwind/actions-runner-dind
      env:
        # Sets the respective default-address-pools fields within dockerd daemon.json
        # See https://github.com/actions/actions-runner-controller/pull/1971 for more information.
        # Also see https://github.com/docker/docs/issues/8663 for the default base/size values in dockerd.
        - name: DOCKER_DEFAULT_ADDRESS_POOL_BASE
          value: "172.17.0.0/12"
        - name: DOCKER_DEFAULT_ADDRESS_POOL_SIZE
          value: "24"

More options can be configured by mounting a configmap to the daemon.json location:

• rootless: /home/runner/.config/docker/daemon.json
• rootful: /etc/docker/daemon.json

apiVersion: actions.summerwind.dev/v1alpha1
kind: RunnerDeployment
metadata:
  name: example-runnerdeployment
spec:
  template:
    spec:
      dockerdWithinRunnerContainer: true
      image: summerwind/actions-runner-dind(-rootless)
      volumeMounts:
        - mountPath: /home/runner/.config/docker/daemon.json
          name: daemon-config-volume
          subPath: daemon.json
      volumes:
        - name: daemon-config-volume
          configMap:
            name: daemon-cm
            items:
              - key: daemon.json
                path: daemon.json
      securityContext:
        fsGroup: 1001 # runner user id

apiVersion: v1
kind: ConfigMap
metadata:
  name: daemon-cm
data:
  daemon.json: |
    {
      "log-level": "warn",
      "dns": ["x.x.x.x"]
    }