App Engine Flex Deployment Health Check Fails

I've made a Python 3 Flask app to serve as an API proxy with gunicorn. I've deployed the openapi to Cloud Endpoints and filled in the endpoints service in the app.yaml file. When

Solution 1:

You can both disable Health Checks or customize them:

For disabling you have to add the following to your app.yaml:

health_check: enable_health_check: False

For customize them you can take a look into the Split health checks.

You can customize Liveness checks request by adding an optional liveness_check section on you app.yaml file, for example:

liveness_check: path: "/liveness_check" check_interval_sec: 30 timeout_sec: 4 failure_threshold: 2 success_threshold: 2

In the documentation you can check the settings available for liveness checks.

In addition, there are the Readiness checks. In the same way, you can customize some settings, for example:

readiness_check: path: "/readiness_check" check_interval_sec: 5 timeout_sec: 4 failure_threshold: 2 success_threshold: 2 app_start_timeout_sec: 300

The values above mentioned can be changed according to your needs. Check this values especially since App Engine Flexible takes some minutes to get the instance startup-ed, this is a remarkable difference to App Engine Standard and should not be taken lightly.

If you examine the nginx.health_check logs for your application, you might see health check polling happening more frequently than you have configured, due to the redundant health checkers that are also following your settings. These redundant health checkers are created automatically and you cannot configure them.