How have you handled failed deployments?

Here is a suggested answer to the DevOps interview question "How have you handled failed deployments?":

Handling Failed Deployments

When a deployment fails, it's critical to act quickly to identify the root cause, mitigate any issues, and get the system back online as soon as possible. Here are the key steps I follow when handling a failed deployment:

1. Assess the Situation

• Determine the scope of the failure - is it impacting the entire system or just certain components?
• Identify any error messages or logs that provide clues about what went wrong.
• Assess the business impact and urgency of restoring service.

2. Rollback or Rollforward

• If the failure is isolated and the previous version is stable, perform an immediate rollback to restore service.
• If the failure is more complex, consider rolling forward with a fix. But only if you are highly confident it will resolve the issue.

3. Investigate the Root Cause

• Dive into the deployment logs, application logs, and monitoring data to pinpoint the root cause.
• Reproduce the failure in a test environment if possible.
• Determine if the issue was caused by the code, infrastructure, config...