Lab to demonstrate how container healthchecks improve reliability of deployments.

After the deployment pipeline has been configured, a health check should be added to the task definition for the dogs application. The health check should test for the presence of particular file (for example, 1.jpg).

From the IDE, the Dockerfile is intentionally modified to ensure the dog memes don't get pulled in to the image at build time.

The changes are then committed and the pipeline will build the new image and attempt to deploy. Based on the roll out configuration of the dogs service. The new version of dogs, with the missing images, should not make it in to production, the deployment should fail, but their should be at least 50% of the current dogs containers still running, ensuring that there is no loss of service.