Talk to any IT pro for more than a minute about containers, and they’ll tell you that operationalizing these microservices-based workloads at scale requires an orchestration tool. That tool is kubernetes, the go-to container management platform that’s been adopted by nearly every major tech company.
Kubernetes is a suite of open source services that work together to manage, deploy, and scale clustered applications in any infrastructure environment — including public and private clouds, virtual machines, bare metal servers, and hybrid environments. It provides a highly scalable and reliable framework that automates application deployment, scaling, and maintenance for IT teams.
Each cluster is made up of physical or virtual computers called nodes, and each node hosts a set of containers. The cluster’s master node controls the nodes and the overall cluster, overseeing container deployment and replication based on developer-defined requirements. The kube-controller-manager handles control loops that manage the state of the cluster through the kubernetes API server.
Pods are the basic building blocks of Kubernetes, and each pod can run a set of containers simultaneously. A kube-scheduler service keeps track of node capacity and resources and assigns tasks to nodes based on availability. The kube-replication controller ensures that a desired number of pod replicas are always running.
Kubernetes can automatically provision, scale, and monitor containers, but it doesn’t handle the connectivity between them or how they communicate with outside services. Istio, an open source service mesh layer for Kubernetes, helps resolve this challenge by adding a sidecar container to each pod that manages and optimizes the connections between other containers in the same cluster.
