Description

Ensure that Compute Engine VM instances have the Automatic restart setting enabled so that the instance automatically restarts if it terminates unexpectedly due to a non-user-initiated event, such as a host system maintenance failure or a hardware error.

Rationale

Without automatic restart enabled, a VM that terminates unexpectedly due to an infrastructure failure will remain stopped until manually restarted, extending unplanned downtime for the workload running on it. Enabling automatic restart improves the resiliency and availability of the instance without requiring manual intervention after a host-level failure.

Impact

  • Reduces unplanned downtime following host system failures or unexpected terminations

  • Improves the overall availability of workloads running on individual VM instances

  • Does not protect against user-initiated stops, which are unaffected by this setting

Default Value

Automatic restart is enabled by default for new Compute Engine VM instances, but may have been disabled on some instances and should be verified.

Pre-Requisites

  • IAM permissions to view and edit Compute Engine instance settings (e.g., Compute Instance Admin)

Test Plan

  1. Sign in to the Google Cloud Console at https://console.cloud.google.com.

  2. Select the relevant project.

  3. Navigate to Compute Engine > VM instances and select the instance to review.

  4. Open the instance details and locate the Availability policy section.

  5. Verify that Automatic restart is set to On.

  6. If Automatic restart is set to Off, follow the implementation steps.

Implementation Steps

  1. Sign in to the Google Cloud Console at https://console.cloud.google.com.

  2. Select the relevant project.

  3. Navigate to Compute Engine > VM instances and select the instance to update.

  4. Select Edit (note that the instance may need to be stopped for this field to be editable, depending on the field).

  5. Under Availability policy, set Automatic restart to On.

  6. Click Save to apply the change.

  7. Confirm the instance details now reflect Automatic restart as On.

Backout Plan

  1. Sign in to the Google Cloud Console at https://console.cloud.google.com.

  2. Select the relevant project.

  3. Navigate to Compute Engine > VM instances and select the affected instance.

  4. Select Edit.

  5. Under Availability policy, set Automatic restart to Off.

  6. Click Save to apply the change.

Reference