Run WebLogic in the Cloud with Kubernetes Operator and Container Engine by Radu Dobrinescu

Enterprises want to migrate their existing workloads to the cloud to gain performance, elasticity, and agility for their applications. However, refactoring those applications as cloud native can be expensive and time consuming. This post shows you how to leverage several Oracle Cloud Infrastructure services to run WebLogic domains for your existing Java EE applications in the cloud and gain these benefits without rewriting the apps.

There are several ways of running WebLogic in Oracle Cloud Infrastructure, from taking a DIY approach to using the Oracle Java Cloud Service. However, running WebLogic on Kubernetes offers a balance among the level of automation, portability, and the ability to customize multiple domains. Creating and managing multiple domains in a Kubernetes cluster is simplified by the use of the WebLogic Kubernetes Operator, an open source tool that bridges the gap between the WebLogic administrative tools and modern solutions for management and monitoring applications, such as ELK Stack (Elastic Stack), Prometheus, and Grafana.

Architecture Overview

This end-to-end solution for running WebLogic domains that follow the Maximum Availability Architecture guidelines uses the following Oracle Cloud Infrastructure services:

· Container Engine for Kubernetes: Although the operator supports any generic Kubernetes cluster, in this post we use the Container Engine for Kubernetes (sometimes abbreviated OKE). The Container Engine for Kubernetes cluster has three worker nodes spread out on different physical infrastructure, so that the WebLogic clusters themselves have the highest availability.

· File Storage: To further comply with best practices for running WebLogic domains, the domain configuration files are stored on shared storage that is accessible from all WebLogic servers in the cluster, on File Storage. This setup offers the following advantages: you don’t need to rebuild Docker images for changes in the domain configuration, backup is faster and centralized, and logs are stored by default on persistent storage.

· Load Balancing: By default, the WebLogic servers (admin or clustered managed servers) created by the operator are not exposed outside the Container Engine for Kubernetes cluster, so to expose an application to the outside world, we use the Load Balancing service.

· Registry: Optionally, the Docker images can be stored in a private Oracle Cloud Infrastructure Registry repository.