Tutorial: Deploy self-hosted CI/CD runners and agents with Azure Container Apps jobs

In this tutorial, you learn how to run GitHub Actions runners as an event-driven Container Apps job.

In this tutorial, you learn how to run Azure Pipelines agents as an event-driven Container Apps job.

• Azure DevOps organization: If you don't have a DevOps organization with an active subscription, you can create one for free.

Create a GitHub repository for running a workflow

To execute a workflow, you need to create a GitHub repository that contains the workflow definition.

1. Navigate to GitHub and sign in.

2. Create a new repository by entering the following values.

   Setting	Value
   Owner	Select your GitHub username.
   Repository name	Enter a name for your repository.
   Visibility	Select Private.
   Initialize this repository with	Select Add a README file.

   Leave the rest of the values as their default selection.

3. Select Create repository.

4. In your new repository, select Actions.

5. Search for the Simple workflow template and select Configure.

6. Select Commit changes to add the workflow to your repository.

The workflow runs on the ubuntu-latest GitHub-hosted runner and prints a message to the console. Later, you replace the GitHub-hosted runner with a self-hosted runner.

Get a GitHub personal access token

To run a self-hosted runner, you need to create a personal access token (PAT) in GitHub. Each time a runner starts, the PAT is used to generate a token to register the runner with GitHub. The PAT is also used by the GitHub Actions runner scale rule to monitor the repository's workflow queue and start runners as needed.

1. In GitHub, select your profile picture in the upper-right corner and select Settings.

2. Select Developer settings.

3. Under Personal access tokens, select Fine-grained tokens.

4. Select Generate new token.

5. In the New fine-grained personal access token screen, enter the following values.

   Setting	Value
   Token name	Enter a name for your token.
   Expiration	Select 30 days.
   Repository access	Select Only select repositories and select the repository you created.

   Enter the following values for Repository permissions.

   Setting	Value
   Actions	Select Read-only.
   Administration	Select Read and write.
   Metadata	Select Read-only.

6. Select Generate token.

7. Copy the token value.

8. Define variables that are used to configure the runner and scale rule later.

   • Bash
   • PowerShell

   GITHUB_PAT="<GITHUB_PAT>"
   REPO_OWNER="<REPO_OWNER>"
   REPO_NAME="<REPO_NAME>"
   

   Replace the placeholders with the following values:

   Placeholder	Value
   <GITHUB_PAT>	The GitHub PAT you generated.
   <REPO_OWNER>	The owner of the repository you created earlier. This value is usually your GitHub username.
   <REPO_NAME>	The name of the repository you created earlier. This value is the same name you entered in the Repository name field.

Build the GitHub Actions runner container image

To create a self-hosted runner, you need to build a container image that executes the runner. In this section, you build the container image and push it to a container registry.

1. Define a name for your container image and registry.

   • Bash
   • PowerShell

   CONTAINER_IMAGE_NAME="github-actions-runner:1.0"
   CONTAINER_REGISTRY_NAME="<CONTAINER_REGISTRY_NAME>"
   

   Replace <CONTAINER_REGISTRY_NAME> with a unique name for creating a container registry. Container registry names must be unique within Azure and be from 5 to 50 characters in length containing numbers and lowercase letters only.

2. Create a container registry.

   • Bash
   • PowerShell

   az acr create \
       --name "$CONTAINER_REGISTRY_NAME" \
       --resource-group "$RESOURCE_GROUP" \
       --location "$LOCATION" \
       --sku Basic \
       --admin-enabled true
   

3. The Dockerfile for creating the runner image is available on GitHub. Run the following command to clone the repository and build the container image in the cloud using the az acr build command.

   • Bash
   • PowerShell

   az acr build \
       --registry "$CONTAINER_REGISTRY_NAME" \
       --image "$CONTAINER_IMAGE_NAME" \
       --file "Dockerfile.github" \
       "https://github.com/Azure-Samples/container-apps-ci-cd-runner-tutorial.git"
   

   The image is now available in the container registry.

Deploy a self-hosted runner as a job

You can now create a job that uses to use the container image. In this section, you create a job that executes the self-hosted runner and authenticates with GitHub using the PAT you generated earlier. The job uses the github-runner scale rule to create job executions based on the number of pending workflow runs.

1. Create a job in the Container Apps environment.

   • Bash
   • PowerShell

   az containerapp job create -n "$JOB_NAME" -g "$RESOURCE_GROUP" --environment "$ENVIRONMENT" \
       --trigger-type Event \
       --replica-timeout 1800 \
       --replica-retry-limit 0 \
       --replica-completion-count 1 \
       --parallelism 1 \
       --image "$CONTAINER_REGISTRY_NAME.azurecr.cn/$CONTAINER_IMAGE_NAME" \
       --min-executions 0 \
       --max-executions 10 \
       --polling-interval 30 \
       --scale-rule-name "github-runner" \
       --scale-rule-type "github-runner" \
       --scale-rule-metadata "githubAPIURL=https://api.github.com" "owner=$REPO_OWNER" "runnerScope=repo" "repos=$REPO_NAME" "targetWorkflowQueueLength=1" \
       --scale-rule-auth "personalAccessToken=personal-access-token" \
       --cpu "2.0" \
       --memory "4Gi" \
       --secrets "personal-access-token=$GITHUB_PAT" \
       --env-vars "GITHUB_PAT=secretref:personal-access-token" "GH_URL=https://github.com/$REPO_OWNER/$REPO_NAME" "REGISTRATION_TOKEN_API_URL=https://api.github.com/repos/$REPO_OWNER/$REPO_NAME/actions/runners/registration-token" \
       --registry-server "$CONTAINER_REGISTRY_NAME.azurecr.cn"
   

   The following table describes the key parameters used in the command.

   Parameter	Description
   --replica-timeout	The maximum duration a replica can execute.
   --replica-retry-limit	The number of times to retry a failed replica.
   --replica-completion-count	The number of replicas to complete successfully before a job execution is considered successful.
   --parallelism	The number of replicas to start per job execution.
   --min-executions	The minimum number of job executions to run per polling interval.
   --max-executions	The maximum number of job executions to run per polling interval.
   --polling-interval	The polling interval at which to evaluate the scale rule.
   --scale-rule-name	The name of the scale rule.
   --scale-rule-type	The type of scale rule to use. To learn more about the GitHub runner scaler, see the KEDA documentation.
   --scale-rule-metadata	The metadata for the scale rule. If you're using GitHub Enterprise, update githubAPIURL with its API URL.
   --scale-rule-auth	The authentication for the scale rule.
   --secrets	The secrets to use for the job.
   --env-vars	The environment variables to use for the job.
   --registry-server	The container registry server to use for the job. For an Azure Container Registry, the command automatically configures authentication.

   The scale rule configuration defines the event source to monitor. It's evaluated on each polling interval and determines how many job executions to trigger. To learn more, see Set scaling rules.

The event-driven job is now created in the Container Apps environment.

Run a workflow and verify the job

The job is configured to evaluate the scale rule every 30 seconds. During each evaluation, it checks the number of pending workflow runs that require a self-hosted runner and starts a new job execution for pending workflow, up to a configured maximum of 10 executions.

To verify the job was configured correctly, you modify the workflow to use a self-hosted runner and trigger a workflow run. You can then view the job execution logs to see the workflow run.

1. In the GitHub repository, navigate to the workflow you generated earlier. It's a YAML file in the .github/workflows directory.

2. Select Edit in place.

3. Update the runs-on property to self-hosted:

   runs-on: self-hosted
   

4. Select Commit changes....

5. Select Commit changes.

6. Navigate to the Actions tab.

   A new workflow is now queued. Within 30 seconds, the job execution will start and the workflow will complete soon after.

   Wait for the action to complete before going on the next step.

7. List the executions of the job to confirm a job execution was created and completed successfully.

   • Bash
   • PowerShell

   az containerapp job execution list \
       --name "$JOB_NAME" \
       --resource-group "$RESOURCE_GROUP" \
       --output table \
       --query '[].{Status: properties.status, Name: name, StartTime: properties.startTime}'
   

Create an Azure DevOps project and repository

To execute a pipeline, you need an Azure DevOps project and repository.

1. Navigate to Azure DevOps and sign in to your account.

2. Select an existing organization or create a new one.

3. In the organization overview page, select New project and enter the following values.

   Setting	Value
   Project name	Enter a name for your project.
   Visibility	Select Private.

4. Select Create.

5. From the side navigation, select Repos.

6. Under Initialize main branch with a README or .gitignore, select Add a README.

7. Leave the rest of the values as defaults and select Initialize.

Create a new agent pool

Create a new agent pool to run the self-hosted runner.

1. In your Azure DevOps project, expand the left navigation bar and select Project settings.

   

2. Under the Pipelines section in the Project settings navigation menu, select Agent pools.

   

3. Select Add pool and enter the following values.

   Setting	Value
   Pool to link	Select New.
   Pool type	Select Self-hosted.
   Name	Enter container-apps.
   Grant access permission to all pipelines	Select this checkbox.

4. Select Create.

Get an Azure DevOps personal access token

To run a self-hosted runner, you need to create a personal access token (PAT) in Azure DevOps. The PAT is used to authenticate the runner with Azure DevOps. It's also used by the scale rule to determine the number of pending pipeline runs and trigger new job executions.

[!NOTE]

Personal Access Tokens (PATs) have an expiration date. Regularly rotate your tokens to ensure they remain valid (not expired) to maintain uninterrupted service.

1. In Azure DevOps, select User settings next to your profile picture in the upper-right corner.

2. Select Personal access tokens.

3. In the Personal access tokens page, select New Token and enter the following values.

   Setting	Value
   Name	Enter a name for your token.
   Organization	Select the organization you chose or created earlier.
   Scopes	Select Custom defined.
   Show all scopes	Select Show all scopes.
   Agent Pools (Read & manage)	Select Agent Pools (Read & manage).

   Leave all other scopes unselected.

4. Select Create.

5. Copy the token value to a secure location.

   You can't retrieve the token after you leave the page.

6. Define variables that are used to configure the Container Apps jobs later.

   • Bash
   • PowerShell

   AZP_TOKEN="<AZP_TOKEN>"
   ORGANIZATION_URL="<ORGANIZATION_URL>"
   AZP_POOL="container-apps"
   

   Replace the placeholders with the following values:

   Placeholder	Value	Comments
   <AZP_TOKEN>	The Azure DevOps PAT you generated.
   <ORGANIZATION_URL>	The URL of your Azure DevOps organization. Make sure no trailing / is present at the end of the URL.	For example, https://dev.azure.com/myorg or https://myorg.visualstudio.com.

Build the Azure Pipelines agent container image

To create a self-hosted agent, you need to build a container image that runs the agent. In this section, you build the container image and push it to a container registry.

1. Back in your terminal, define a name for your container image and registry.

   • Bash
   • PowerShell

   CONTAINER_IMAGE_NAME="azure-pipelines-agent:1.0"
   CONTAINER_REGISTRY_NAME="<CONTAINER_REGISTRY_NAME>"
   

   Replace <CONTAINER_REGISTRY_NAME> with a unique name for creating a container registry.

   Container registry names must be unique within Azure and be from 5 to 50 characters in length containing numbers and lowercase letters only.

2. Create a container registry.

   • Bash
   • PowerShell

   az acr create \
       --name "$CONTAINER_REGISTRY_NAME" \
       --resource-group "$RESOURCE_GROUP" \
       --location "$LOCATION" \
       --sku Basic \
       --admin-enabled true
   

3. The Dockerfile for creating the runner image is available on GitHub. Run the following command to clone the repository and build the container image in the cloud using the az acr build command.

   • Bash
   • PowerShell

   az acr build \
       --registry "$CONTAINER_REGISTRY_NAME" \
       --image "$CONTAINER_IMAGE_NAME" \
       --file "Dockerfile.azure-pipelines" \
       "https://github.com/Azure-Samples/container-apps-ci-cd-runner-tutorial.git"
   

   The image is now available in the container registry.

Create a placeholder self-hosted agent

Before you can run a self-hosted agent in your new agent pool, you need to create a placeholder agent. The placeholder agent ensures the agent pool is available. Pipelines that use the agent pool fail when there's no placeholder agent.

You can run a manual job to register an offline placeholder agent. The job runs once and can be deleted. The placeholder agent doesn't consume any resources in Azure Container Apps or Azure DevOps.

1. Create a manual job in the Container Apps environment that creates the placeholder agent.

   • Bash
   • PowerShell

   az containerapp job create -n "$PLACEHOLDER_JOB_NAME" -g "$RESOURCE_GROUP" --environment "$ENVIRONMENT" \
       --trigger-type Manual \
       --replica-timeout 300 \
       --replica-retry-limit 0 \
       --replica-completion-count 1 \
       --parallelism 1 \
       --image "$CONTAINER_REGISTRY_NAME.azurecr.cn/$CONTAINER_IMAGE_NAME" \
       --cpu "2.0" \
       --memory "4Gi" \
       --secrets "personal-access-token=$AZP_TOKEN" "organization-url=$ORGANIZATION_URL" \
       --env-vars "AZP_TOKEN=secretref:personal-access-token" "AZP_URL=secretref:organization-url" "AZP_POOL=$AZP_POOL" "AZP_PLACEHOLDER=1" "AZP_AGENT_NAME=placeholder-agent" \
       --registry-server "$CONTAINER_REGISTRY_NAME.azurecr.cn"
   

   The following table describes the key parameters used in the command.

   Parameter	Description
   --replica-timeout	The maximum duration a replica can execute.
   --replica-retry-limit	The number of times to retry a failed replica.
   --replica-completion-count	The number of replicas to complete successfully before a job execution is considered successful.
   --parallelism	The number of replicas to start per job execution.
   --secrets	The secrets to use for the job.
   --env-vars	The environment variables to use for the job.
   --registry-server	The container registry server to use for the job. For an Azure Container Registry, the command automatically configures authentication.

   Setting the AZP_PLACEHOLDER environment variable configures the agent container to register as an offline placeholder agent without running a job.

2. Execute the manual job to create the placeholder agent.

   • Bash
   • PowerShell

   az containerapp job start -n "$PLACEHOLDER_JOB_NAME" -g "$RESOURCE_GROUP"
   

3. List the executions of the job to confirm a job execution was created and completed successfully.

   • Bash
   • PowerShell

   az containerapp job execution list \
       --name "$PLACEHOLDER_JOB_NAME" \
       --resource-group "$RESOURCE_GROUP" \
       --output table \
       --query '[].{Status: properties.status, Name: name, StartTime: properties.startTime}'
   

4. Verify the placeholder agent was created in Azure DevOps.

   1. In Azure DevOps, navigate to your project.
   2. Select Project settings > Agent pools > container-apps > Agents.
   3. Confirm that a placeholder agent named placeholder-agent is listed and its status is offline.

5. The job isn't needed again. You can delete it.

   • Bash
   • PowerShell

   az containerapp job delete -n "$PLACEHOLDER_JOB_NAME" -g "$RESOURCE_GROUP"
   

Create a self-hosted agent as an event-driven job

Now that you have a placeholder agent, you can create a self-hosted agent. In this section, you create an event-driven job that runs a self-hosted agent when a pipeline is triggered.

az containerapp job create -n "$JOB_NAME" -g "$RESOURCE_GROUP" --environment "$ENVIRONMENT" \
    --trigger-type Event \
    --replica-timeout 1800 \
    --replica-retry-limit 0 \
    --replica-completion-count 1 \
    --parallelism 1 \
    --image "$CONTAINER_REGISTRY_NAME.azurecr.cn/$CONTAINER_IMAGE_NAME" \
    --min-executions 0 \
    --max-executions 10 \
    --polling-interval 30 \
    --scale-rule-name "azure-pipelines" \
    --scale-rule-type "azure-pipelines" \
    --scale-rule-metadata "poolName=$AZP_POOL" "targetPipelinesQueueLength=1" \
    --scale-rule-auth "personalAccessToken=personal-access-token" "organizationURL=organization-url" \
    --cpu "2.0" \
    --memory "4Gi" \
    --secrets "personal-access-token=$AZP_TOKEN" "organization-url=$ORGANIZATION_URL" \
    --env-vars "AZP_TOKEN=secretref:personal-access-token" "AZP_URL=secretref:organization-url" "AZP_POOL=$AZP_POOL" \
    --registry-server "$CONTAINER_REGISTRY_NAME.azurecr.cn"

az containerapp job create -n "$JOB_NAME" -g "$RESOURCE_GROUP" --environment "$ENVIRONMENT" `
    --trigger-type Event `
    --replica-timeout 1800 `
    --replica-retry-limit 0 `
    --replica-completion-count 1 `
    --parallelism 1 `
    --image "$CONTAINER_REGISTRY_NAME.azurecr.cn/$CONTAINER_IMAGE_NAME" `
    --min-executions 0 `
    --max-executions 10 `
    --polling-interval 30 `
    --scale-rule-name "azure-pipelines" `
    --scale-rule-type "azure-pipelines" `
    --scale-rule-metadata "poolName=$AZP_POOL" "targetPipelinesQueueLength=1" `
    --scale-rule-auth "personalAccessToken=personal-access-token" "organizationURL=organization-url" `
    --cpu "2.0" `
    --memory "4Gi" `
    --secrets "personal-access-token=$AZP_TOKEN" "organization-url=$ORGANIZATION_URL" `
    --env-vars "AZP_TOKEN=secretref:personal-access-token" "AZP_URL=secretref:organization-url" "AZP_POOL=$AZP_POOL" `
    --registry-server "$CONTAINER_REGISTRY_NAME.azurecr.cn"

The following table describes the scale rule parameters used in the command.

The scale rule configuration defines the event source to monitor. It's evaluated on each polling interval and determines how many job executions to trigger. To learn more, see Set scaling rules.

The event-driven job is now created in the Container Apps environment.

Run a pipeline and verify the job

Now that you've configured a self-hosted agent job, you can run a pipeline and verify it's working correctly.

1. In the left-hand navigation of your Azure DevOps project, navigate to Pipelines.

2. Select Create pipeline.

3. Select Azure Repos Git as the location of your code.

4. Select the repository you created earlier.

5. Select Starter pipeline.

6. In the pipeline YAML, change the pool from vmImage: ubuntu-latest to name: container-apps.

   pool:
     name: container-apps
   

7. Select Save and run.

   The pipeline runs and uses the self-hosted agent job you created in the Container Apps environment.

8. List the executions of the job to confirm a job execution was created and completed successfully.

   • Bash
   • PowerShell

   az containerapp job execution list \
       --name "$JOB_NAME" \
       --resource-group "$RESOURCE_GROUP" \
       --output table \
       --query '[].{Status: properties.status, Name: name, StartTime: properties.startTime}'