Containers & Pods

There are many cases where our users want to run pods with multiple containers within OpenShift. A common use-case for running multiple containers is where a pod has a 'primary' container that does some job, and a 'side-car' container that does something like write logs to a logging agent.

The motivation for pods is twofold -- to make it easier to share resources between containers, and to enable deploying and replicating groups of containers that share resources. You can read more about them in the user-guide.

The reason we still use a Pod when only a single container is that containers do not have all the notions that are attached to pods. For example, pods have IP addresses. Containers do not -- they share the IP address associated with the pod's network namespace.

https://stackoverflow.com/questions/34061851/why-using-pods-and-not-directly-containers-in-an-openshift-v3-environment