Why do I need a Kubernetes cluster?

At its core, Kubernetes is a container scheduler, but it is a much richer and fully featured toolkit that has many other features. It is possible to extend and augment the functionality that Kubernetes provides, as products such as RedHat's OpenShift have done. Kubernetes also allows you to extend it's core functionality yourself by deploying add-on tools and services to your cluster.

Here are some of the key features that are built into Kubernetes:

• Self-healing: Kubernetes controller-based orchestration ensures that containers are restarted when they fail, and rescheduled when the nodes they are running on fail. User-defined health checks allow users to make decisions about how and when to recover from failing services, and how to direct traffic when they do.
• Service discovery: Kubernetes is designed from the ground up to make service discovery simple without needing to make modifications to your applications. Each instance of your application gets its own IP address, and standard discovery mechanisms such as DNS and load balancing let your services communicate.
• Scaling: Kubernetes makes horizontal scaling possible at the push of a button, and also provides autoscaling facilities.
• Deployment orchestration: Kubernetes not only helps you to manage running applications, but has tools to roll out changes to your application and its configuration. Its flexibility allows you to build complex deployment patterns for yourself or to use one of a number of add-on tools.
• Storage management: Kubernetes has built-in support for managing the underlying storage technology on cloud providers, such as AWS Elastic Block Store volumes, as well as other standard networked storage tools, such as NFS.
• Cluster optimization: The Kubernetes scheduler automatically assigns your workloads to machines based on their requirements, allowing for better utilization of resources.
• Batch workloads: As well as long-running workloads, Kubernetes can also manage batch jobs, such as CI, batch processing, and cron jobs.