Recently I have been asked a lot of similar questions like “does it make sense to invest in deploying legacy technology on kubernetes?”. Well, first of all, I have to say that some technologies that are considered “legacy” have tons of new exciting features for the new workloads and applications. This is, for example, the case of DB2 with spatial queries and many others that you may have a look at (to be honest, I have very few experience with it).

Spring Boot is extensively used for microservice architectures, most of them running in kubernetes. Spring Cache has been defined as an abstraction layer for cache servers, although there are other alternatives (JSR-107 JCache was one of the initial ones). When using a cache, there are two alternatives, embedded in the microservice or external to it. Both has its benefits and drawbacks and depending on the use case one is prefered

Infinispan is a java based open source cache and grid solution, that is used extensively in different framework like j2ee, springboot and quarkus among others. It is compatible with different java caching models, like JSR-107 and spring data. It is very simple to set up a high availability cluster with different replication/distribution configurations, and thanks to the kubernetes operator pattern, is even easier in kubernetes distribution. Prometheus is the defacto standard for metric scraping and short-term storing to identify potential issues.