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OpenShift introduction and basic terminology


I am starting learning few more things from today onwards. Which are one of the most demanded technology now a days & terminology namely - Container | Docker | Podman | OpenShift. Red Hat official training under guidance of Mr. Vimal Daga.
Today's learning :-
  • There are 4 ways of OS(Operating System) provisioning we have - 1. Bare-Metal(Install OS directly on physical hardware), 2. Virtualization(VM), 3. Cloud(Instance), 4. Containerization(container).
  • Here I'll focus on Containerization technology, containers & container orchestration.
  • Containerization is the fastest way of OS provisioning, we can launch a full flash and ready to use OS just within few seconds. Which is known as Container.
  • The host on which we install Docker/Podman is known as Docker/Podman host.
  • The role of Docker is just to launch an OS.
  • Docker is doing great whatever it was created for, but still there was few things those needs to be upgraded, and then a tool named Podman came in market which is an upgraded version of Docker.
  • Docker has a services/daemon dockerd in background, so if the service is running, your environment is up and running and if somehow the service has been stopped/crashed/hacked your whole environment went down.
  • Even though Docker is very fast but since Podman doesn't have any service there are no chance of service stopped/crashed/hacked, that is the reason Podman is more faster/secure/available than Docker.
  • Very important, it is not like Docker has these limitations, actually docker didn't create for this. Very simple the role of docker is to just launch container, that's it task has been completed.
  • We have different solutions available for containerization, like Docker, Podman and LXC etc. But to use container technology more efficiently and reliable we need a product/tool which provides following - 1. Launch container, 2. Collect metric(Manager resources), 3. Container Monitoring, 4. Reporting, 5. High Availability(HA), 6. Auto scaling, 7. Continuous Integration / Continuous Development(CI / CD) etc.
  • There are many products available which can fill all above requirements but here I'll learn one of the most famous and demanded product available from Red hat - OpenShift.
  •  OpenShift is a Private cloud based Platform as a service(PaaS) complete container platform and has capability to provide all above mentioned services. Also it is DevOps tool.
How to install Podman :- 
[root@localhost ]#  yum install podman -y
Or
[root@localhost ]#  yum module install container-tools -y
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