Quickstart for Actions Runner Controller

In this tutorial, you'll try out the basics of Actions Runner Controller.

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Introduction

Actions Runner Controller (ARC) は、GitHub Actions のセルフホステッド ランナーを調整およびスケーリングする Kubernetes オペレーターです。 詳細については、Kubernetes ドキュメントの「オペレーター パターン」を参照してください。

ARC を使うと、リポジトリ、組織、またはエンタープライズで実行中のワークフローの数に基づいて自動的にスケーリングされるランナー スケール セットを作成できます。 制御されたランナーは一時的でコンテナーに基づく可能性があるため、新しいランナー インスタンスを迅速かつクリーンにスケールアップまたはスケールダウンすることができます。 自動スケーリングの詳細については、「セルフホステッド ランナーによる自動スケーリング」を参照してください。

You can set up ARC on Kubernetes using Helm, then create and run a workflow that uses runner scale sets. For more information about runner scale sets, see アクション ランナー コントローラーを使用してランナー スケール セットをデプロイする.

Prerequisites

In order to use ARC, ensure you have the following.

  • A Kubernetes cluster

    • For a managed cloud environment, you can use AKS. For more information, see Azure Kubernetes Service in the Azure documentation.

    • For a local setup, you can use minikube or kind. For more information, see minikube start in the minikube documentation and kind in the kind documentation.

      メモ

      OpenShift clusters are currently unsupported.

  • Helm 3

  • While it is not required for ARC to be deployed, we recommend ensuring you have implemented a way to collect and retain logs from the controller, listeners, and ephemeral runners before deploying ARC in production workflows.

Installing Actions Runner Controller

  1. To install the operator and the custom resource definitions (CRDs) in your cluster, do the following.

    1. In your Helm chart, update the NAMESPACE value to the location you want your operator pods to be created. This namespace must allow access to the Kubernetes API server.
    2. Install the Helm chart.

    The following example installs the latest version of the chart. To install a specific version, you can pass the --version argument along with the version of the chart you wish to install. You can find the list of releases in the GitHub Container Registry.

    Bash
    NAMESPACE="arc-systems"
helm install arc \
    --namespace "${NAMESPACE}" \
    --create-namespace \
    oci://ghcr.io/actions/actions-runner-controller-charts/gha-runner-scale-set-controller

    For additional Helm configuration options, see values.yaml in the ARC documentation.

  2. To enable ARC to authenticate to GitHub, generate a personal access token (classic). For more information, see GitHub API に対する認証を行う.

Configuring a runner scale set

  1. To configure your runner scale set, run the following command in your terminal, using values from your ARC configuration.

    When you run the command, keep the following in mind.

    • Update the INSTALLATION_NAME value carefully. You will use the installation name as the value of runs-on in your workflows. For more information, see GitHub Actions　のワークフロー構文.

    • Update the NAMESPACE value to the location you want the runner pods to be created.

    • Set GITHUB_CONFIG_URL to the URL of your repository, organization, or enterprise. This is the entity that the runners will belong to.

    • This example command installs the latest version of the Helm chart. To install a specific version, you can pass the --version argument with the version of the chart you wish to install. You can find the list of releases in the GitHub Container Registry.

      メモ

      • セキュリティのベスト プラクティスとして、オペレーター ポッドを含む名前空間とは異なる名前空間にランナー ポッドを作成します。
      • セキュリティのベスト プラクティスとして、Kubernetes シークレットを作成し、シークレット参照を渡します。 CLI を介してプレーンテキストでシークレットを渡すと、セキュリティ上のリスクが生じる可能性があります。 For more information, see アクション ランナー コントローラーを使用してランナー スケール セットをデプロイする.
      Bash
      INSTALLATION_NAME="arc-runner-set"
NAMESPACE="arc-runners"
GITHUB_CONFIG_URL="http://github.com/<your_enterprise/org/repo>"
GITHUB_PAT="<PAT>"
helm install "${INSTALLATION_NAME}" \
    --namespace "${NAMESPACE}" \
    --create-namespace \
    --set githubConfigUrl="${GITHUB_CONFIG_URL}" \
    --set githubConfigSecret.github_token="${GITHUB_PAT}" \
    oci://ghcr.io/actions/actions-runner-controller-charts/gha-runner-scale-set

      For additional Helm configuration options, see values.yaml in the ARC documentation.

  2. From your terminal, run the following command to check your installation.

    Bash
    helm list -A

    You should see an output similar to the following.

    NAME            NAMESPACE       REVISION        UPDATED                                 STATUS          CHART                                       APP VERSION
arc             arc-systems     1               2023-04-12 11:45:59.152090536 +0000 UTC deployed        gha-runner-scale-set-controller-0.4.0       0.4.0
arc-runner-set  arc-runners     1               2023-04-12 11:46:13.451041354 +0000 UTC deployed        gha-runner-scale-set-0.4.0                  0.4.0

  3. To check the manager pod, run the following command in your terminal.

    Bash
    kubectl get pods -n arc-systems

    If everything was installed successfully, the status of the pods shows as Running.

    NAME                                                   READY   STATUS    RESTARTS   AGE
arc-gha-runner-scale-set-controller-594cdc976f-m7cjs   1/1     Running   0          64s
arc-runner-set-754b578d-listener                       1/1     Running   0          12s

If your installation was not successful, see Actions Runner Controller エラーのトラブルシューティング for troubleshooting information.

Using runner scale sets

Now you will create and run a simple test workflow that uses the runner scale set runners.

  1. In a repository, create a workflow similar to the following example. The runs-on value should match the Helm installation name you used when you installed the autoscaling runner set.

    For more information on adding workflows to a repository, see GitHub Actions のクイックスタート.

    YAML
    name: Actions Runner Controller Demo
on:
  workflow_dispatch:

jobs:
  Explore-GitHub-Actions:
    # You need to use the INSTALLATION_NAME from the previous step
    runs-on: arc-runner-set
    steps:
    - run: echo "🎉 This job uses runner scale set runners!"

  2. Once you've added the workflow to your repository, manually trigger the workflow. For more information, see ワークフローの手動実行.

  3. To view the runner pods being created while the workflow is running, run the following command from your terminal.

    Bash
    kubectl get pods -n arc-runners

    A successful output will look similar to the following.

    NAMESPACE     NAME                                                  READY   STATUS    RESTARTS      AGE
arc-runners   arc-runner-set-rmrgw-runner-p9p5n                     1/1     Running   0             21s

Next steps

Actions Runner Controller can help you efficiently manage your GitHub Actions runners. Ready to get started? Here are some helpful resources for taking your next steps with ARC:

Apache-2.0 ライセンスのもとで http://github.com/actions/actions-runner-controller/ から一部を引用しています。

Copyright 2019 Moto Ishizawa

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    http://www.apache.org/licenses/LICENSE-2.0

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