Kubernetes Glossary

DigitalOcean Kubernetes (DOKS) is a managed Kubernetes service that lets you deploy Kubernetes clusters without the complexities of handling the control plane and containerized infrastructure. Clusters are compatible with standard Kubernetes toolchains, integrate natively with DigitalOcean Load Balancers and volumes, and can be managed programmatically using the API and command line. For critical workloads, add the high-availability control plane to increase uptime with 99.95% SLA.

This glossary defines the core concepts behind Kubernetes to help build your mental model of how Kubernetes work and understand what the documentation is referring to when it uses certain terminology.

Cluster networking is highly-coupled container-to-container, pod-to-pod, pod-to-service, or external-to-service communication.
Feature gates are key-value pairs that describe upstream Kubernetes features.
High Availability (HA) is an approach to infrastructure design focusing on reducing downtime and eliminating single points of failure.
High-availability control plane is a control plane that has multiple replicas of each control plane component.
A container image, Docker image, or image, is a static file containing executable code that cannot be changed.
kubectl is a command-line interface (CLI) used to run commands on Kubernetes clusters.
A load balancer distributes traffic across a backend pool of servers to improve the stability and responsiveness of an application.
A node pool is a group of nodes with the same configuration within a cluster.
A pod is the smallest deployable unit of computing that is created and managed by Kubernetes.
Role-based access control (RBAC), also known as role-based security, restricts network access based on the role a user has within an organization.
SSL certificate is a digital document outlining the identity of the website.
Sticky session, or session persistence occurs when the load balancer creates a connection between a network and a user for a direction of the session.
Surge upgrades create duplicate, up to a maximum of 10, nodes during cluster upgrade.
A worker node is a node that runs the application in a cluster and reports to a control plane.