The GitHub Actions Exam (GH-200)

A non-zero exit code is used to set the status of an action to " failed " in GitHub Actions. When the action ' s script or code exits with a non-zero status, it indicates failure, and GitHub will mark the action as failed.

Creating a separate repository for each custom action allows you to manage the versioning independently for each action. This approach provides flexibility, as each action can be updated, tested, and versioned separately, avoiding potential conflicts or dependencies between different actions.

A job using runs-on: [gpu] depends on an available runner matching that label. If the workflow previously succeeded but now remains waiting, the runner ' s availability, registration, connectivity, or label assignment should be investigated. GitHub stores self-hosted runner application diagnostic logs in the runner installation ' s _diag directory; Runner_ log files provide details about runner startup, connectivity, registration, and update activity, making option A useful. Checking the Set up job information from a previous successful run can also identify which runner previously accepted the job, providing a concrete target for investigation. Rotating GITHUB_TOKEN does not repair runner scheduling because job assignment does not depend on manually rotating that workflow token. GitHub-hosted usage limits are similarly unrelated to a custom gpu runner label. Therefore, A and C are appropriate troubleshooting actions.

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The GitHub context exposes the short name of the branch or tag through github.ref_name. For a workflow triggered from a branch named feature-branch, the expression github.ref_name == ' feature-branch ' evaluates to true, allowing the job to run. GitHub also provides github.ref, but that value normally contains the complete Git reference, such as refs/heads/feature-branch, rather than only the short branch name. The properties github.branch_name, github.ref.name, and github.branch.name shown in the other options are not valid GitHub context properties. GitHub evaluates a job-level if expression before sending the job to a runner, making this an appropriate mechanism for conditional deployment execution. Therefore, option B uses the correct context property and comparison syntax.

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The $GITHUB_ENV environment variable is used to set environment variables that persist across steps in a workflow job. By echoing FOO=bar into $GITHUB_ENV, the variable FOO will be available in subsequent steps within the same job.

To use a starter workflow provided by your organization, you need to go to the Actions tab in the repository and select New workflow. This option allows you to either create a new workflow or select from a list of available workflow templates, including starter workflows provided by your organization.

The best design is to use environment-scoped secrets with the same secret name, such as DEPLOY_KEY, in separate environments such as DevCloud and TestCloud. This lets the same reusable deployment logic reference one consistent secret name while the selected environment supplies the correct value. Option A is invalid because GitHub secret names should not be designed around dotted property access, and reusable workflows should not parse secret names dynamically. Option C introduces unnecessary marketplace dependency and weak secret handling. Option D is also wrong because GitHub secrets are opaque strings; ${{ secrets.DEPLOY_KEY.DevCloud }} is not valid secret property access. Reusable workflows can define and receive named secrets through the secrets mapping.

GitHub Actions defines custom environment variables with the YAML env mapping. YAML mappings use a colon between each key and value, so MY_VARIABLE: my-value beneath env: is the correct syntax. The env key can appear at workflow, job, or step scope depending on how broadly the variable should be available. Options A, B, E, and F either use an unsupported key or the wrong assignment syntax. environment is associated with deployment environments when used in GitHub Actions workflow syntax; it is not the key for declaring ordinary environment variables. The vars context is used for configuration variables created through repository, organization, or environment settings, but var: is not the workflow syntax shown here. Therefore, option C correctly defines the requested custom environment variable.

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Using a tag is a best practice because tags are immutable and represent a fixed version of your action. By referencing tags, consumers of your action can be assured they are using a stable and specific version of the action, which helps in avoiding issues with breaking changes.

The commit SHA is another reliable way to specify a particular version of an action. By referencing a specific commit SHA, consumers can ensure they are using exactly the code that was written at that moment, avoiding the potential for changes in the future.