Proper (Java) application life cycle management in Kubernetes
When operating applications in Kubernetes, proper lifecycle management is crucial to enable Kubernetes to manage applications correctly throughout their different phases: startup, runtime and shutdown. Improper or incomplete lifecycle management can lead to incidents with unforeseen and difficult to debug application behavior, such as random CrashLoopBackOffs, broken/zombie services not being restarted or even entire services not becoming healthy after a scheduled restart.
Based on both good and bad applied practices in trivago’s search backend, this article outlines key aspects for lifecycle management of our Java applications running inside docker containers on Kubernetes. Many of these can be applied to other applications independent of the programming language as well.
We touch on the required knowledge briefly and focus on how we applied it in practice while sharing our operational experience with it.