ibmredhat 8 & @OpenShift #container management #devops

ibmredhat 8 & @OpenShift #container management #devops

ibmredhat have removed the Docker container engine, along with the docker command, from Red Hat Enterprise Linux 8 entirely. For RHEL 8, Docker is not included and not supported by Red Hat (although it is still available from other sources)

  • Xhttps://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/pdf/building_running_and_managing_containers/Red_Hat_Enterprise_Linux-8-Building_running_and_managing_containers-en-US.pdfX

with ibmredhat the focus is not on running individual containers from the command line. The primary venue for running containers is a Kubernetes-based platform, such as OpenShift.

By repositioning OpenShift as the project for running containers, container engines like Docker become just another component of OpenShift with no direct access by end users.

Because the container engine in OpenShift is not meant to be used directly, it can be
implemented with a limited feature set that focuses on doing everything that OpenShift needs, without having to implement lots of standalone features

Tools like podman, skopeo, and buildah were developed to take over those docker command features.

the newworld tools are

ibmredhat universal base image (UBI) containers

to build a container run buildah

$ buildah bud -t mycontainer

Dockerfile
FROM registry.access.redhat.com/ubi8/ubi
ADD myecho /usr/local/bin
ENTRYPOINT "/usr/local/bin/myecho"
CMD "/usr/local/bin/myecho"

myecho
echo "This container works!"

to manage, run, stop, start a container use podman

$ podman run -i -t -p 8080:80 --name=pho photon /bin/bash
$ podman inspect --format='{{.Path}}' pho
$ podman logs pho
$ podman stop pho
$ podman start -i -a pho

to copy containers use skopeo

$ skopeo