Is it possible to show a static page if all ELB registered instances are down

After further effort to solve this, I figured out a way to get what I wanted done. Instead of me deploying a war from jenkins manually, I installed jenkins from their RHEL distribution repo and everything seems to be working well.

My setup is:

Internet -> (443) ELB (443) ---> (8080) EC2 Jenkins

ELB has no stickiness enabled and is terminating SSL connections. Connection to Jenkins backend is over HTTP.

Hopefully this will help anyone who wants to run Jenkins directly behind an ELB without a webserver inbetween to proxy.

After a discussion with the support team, it turns out that ECS cannot support our current use case.

There is a workaround that solves one of the issues we are facing. That workaround is to create a separate, essential, health-check container and in the same ECS task as the actual application container. The purpose of the health-check container is to monitor the application container to determine when the application has been started completely. If it detects that the application has failed to start, it exits, causing the ECS service to cycle the task. The ELB is then configured to perform its health checks against the health-check container, which will always report that it is up via the relevant port. This workaround will prevent the ECS service from cycling the ECS task due to failed health checks.

However, the ELB will begin routing traffic to the application container immediately. It will do so, even if the application container is not yet ready to receive traffic (for example, because it is still waiting for a cache to load). Currently, there is no way to delay the ELB from sending traffic to the application container, as the ECS service provides no support a grace period. We have managed to workaround this issue by providing messages to our application containers via SQS and only having them pull from the queue when their caches are fully loaded. However, we have future use cases (such as serving web requests) where this is not a feasible option. To this end, I intend to raise a feature request for the grace period.

As an aside, both Kubernetes (http://kubernetes.io/v1.0/docs/user-guide/walkthrough/k8s201.html#application-health-checking) and Marathon (https://mesosphere.github.io/marathon/docs/health-checks.html) already support this option for health checking, if someone reading this is happy not to use a managed service.