OpenShift

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OpenShift is a Kubernetes distribution from RedHat. It is a complex piece of software that bundles different pieces (monitoring, console-gui, authentication) together. The aim is to support containers in a productive environment with (paid) support by redhat.

Installation

Server

If you want the open source alternative you can use okd free of charge (since version 4 they have the same versioning) - here are the different instructions on how to install it on different architectures - you need at least 5 VMs.

However if you just want to try it you have two easy options

  1. use [learn.openshift.com] to get knowledge about it
  2. install it on your laptop (non productive environment!) - see below

openshift v3

minishiftAUR - Run a single-node OpenShift v3 cluster inside a VM (use VirtualBox or KVM).

openshift v4

codready-containers can be used to install an openshift v4 cluster on your laptop. Altough the manual says that arch linux is not supported it seems to be working fine (version 1.20)

The installation is described here (please check for correct version). The installation asks for sudo rights (maybe not needed?) and will install an openshift cluster on kvm/libvirt. It will add the current user to the libvirt group. One also needs a secret from cloud.redhat.com (account is needed] - look here

the basic steps for installing crc on your computer:

#untar downloaded archive
tar -xJf crc-linux-amd64.tar.xz
#create a bin link so that future versions only need relinking, no new path
ln -s crc-linux-<VERSION>-amd64 bin
#add bin folder to PATH and restart your terminal so that PATH is updated (or source config file)
...
#create base install of crc takes some minutes (will ask for secret)
crc setup
#start openshift cluster
crc start
#get credentials of openshift instance
crc console --credentials
#open console in webbrowser
crc console

Client

origin-clientAUR - Provides the oc command.

Tips and tricks

Troubleshoot network traffic of a container

In Kubernetes, each shares its network layer with other containers in the same pod. You can install a container with tcpdump in the same pod, and then use oc rsh to connect to the container and monitor the traffic.

See Using sidecars to analyze and debug network traffic in OpenShift for more details.