Red Hat OpenShift Administration I: Operating a Production Cluster
Many resources in Kubernetes and RHOCP create or affect pods.
Resources are created imperatively or declaratively. The imperative strategy instructs the cluster what to do. The declarative strategy defines the state that the cluster matches.
The
oc new-appcommand creates resources that are determined via heuristics.The main way to deploy an application is by creating a deployment.
The workload API includes several resources to create pods. The choice between resources depends on for how long and how often the pod needs to run.
A job resource executes a one-time task on the cluster via a pod. The cluster retries the job until it succeeds, or it retries a specified number of attempts.
Resources are organized into projects and are selected via labels.
A route connects a public-facing IP address and a DNS hostname to an internal-facing service IP address. Services provide network access between pods, whereas routes provide network access to pods from users and applications outside the RHOCP cluster.
