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In a previous post, we saw how to leverage Istio Multicluster to deploy an application (bookinfo) on multiple Red Hat OpenShift clusters and apply mesh policies on all of the deployed services. We also saw that the deployment process was relatively complex. In this post we are going to see how Federation V2 can help simplify the process of deploying an application to multiple clusters. Federation V2, as the name suggests, is the evolution of the Kubernetes Federation initiative, after the project was rebooted around the beginning of 2018.

With datacenters spread across the globe, users are increasingly looking at ways to spread their applications and services across multiple locales or clusters. This need is driven by multiple use cases: from providing high availability, spreading load across multiple clusters while being resilient to individual cluster failures; to avoiding provider lock-in by using hybrid cloud … With datacenters spread across the globe, users are increasingly looking at ways to spread their applications and services across multiple locales or clusters.

Deploying applications to a kubernetes cluster is well defined and can in some cases be as simple as kubectl create -f app.yaml. The user’s story to deploy apps across multiple clusters has not been that simple. How should an app workload be distributed? Should the app resources be replicated into all clusters, or replicated into selected clusters or partitioned into clusters? How is the access to clusters managed? What happens if some of the resources, which user wants to distribute pre-exist in all or fewer clusters in some form.