Cloud Platform replaces all HTTP 500, 501, 502, 503 and 504 status code responses served to visitors of your production environments with a generic 503 Service Unavailable response. Displaying the following common response prevents the production environment from leaking error message information:

Temporarily Unavailable

The website that you're trying to reach is having technical difficulties
and is currently unavailable. We are aware of the issue and are working
hard to fix it. Thank you for your patience.

To assist with troubleshooting during development, non-production environments pass all HTTP 5xx status codes through the load balancers back to the requesting client without any replacement. You can review these error messages in your log files, which you can access using the following methods:

• Downloading active log files
• Downloading historical logs
• Streaming log entries in real time
• Log forwarding in Cloud Platform

To learn more about how your infrastructure allocates resources, see Tuning your infrastructure configuration.