Summary

This guide provides a detailed walkthrough for installing a three-node OpenShift Container Platform (OCP) 4.7 cluster using the assisted installer method, which simplifies the setup by eliminating the need for local DNS, load balancer, and dedicated bootstrap node.

Abstract

The article titled "GUIDE: Install OpenShift 4 — The Easy Way — Part 1" is a comprehensive tutorial aimed at demonstrating the installation process of a three-node OCP 4.7 cluster. It outlines the use of the assisted installer to streamline the installation, avoiding the complexities of setting up local DNS, load balancers, and a dedicated bootstrap node. Instead, it utilizes public DNS, VRRP, and repurposes the bootstrap node as a third master node. The guide includes setting up DNS with public records, logging into Red Hat's OpenShift Cluster Manager, creating the cluster with the assisted installer, generating a discovery ISO, and uploading it to a datastore. It also covers the creation of virtual machines on ESXi, bare metal discovery, networking configuration, and the final steps of reviewing and creating the cluster. The installation process is estimated to take about an hour, after which users can log in to the OpenShift Administrator Dashboard. The guide concludes with a link to a second part, which presumably continues with post-installation configurations or advanced settings.

Opinions

The author suggests that using the assisted installer method is an easier approach to installing OCP compared to traditional methods.
The guide promotes the use of public DNS and VRRP as practical alternatives to local DNS and load balancer setups.
By re-provisioning the bootstrap node into a third master node, the guide implies a cost-effective and simplified infrastructure.
The inclusion of a link to a second part of the guide indicates that the author believes in providing comprehensive, multi-part instructions for a complex installation process.
The guide assumes the reader's familiarity with virtualization platforms like ESXi and the concept of using SSH keys for secure operations.

GUIDE: Install OpenShift 4 — The Easy Way — Part 1

This guide will show by example how to install a three-node OCP 4.7 cluster using the assisted installer. All three nodes are assigned both the master and worker roles. This install method removes the need for a local DNS server, load balancer, and dedicated bootstrap node. Instead, we will use public DNS, VRRP, while the installer re-provisions the bootstrap node into our third master node.

Network Layout:

Setup DNS:

Instead of using or setting up a local DNS server this guide will use public DNS. The domain in this example mydc.dev and the DNS records are modified through the NameCheap dashboard. The two IP addresses chosen for the virtual IPs are out of the DHCP range and not currently in use in my network (192.168.60.30 and .31). The cluster name is my example is “lab”.

Add “A Records” for both api.. and *.apps..

Login to cloud.redhat.com:

Browse to https://cloud.redhat.com, and open the OpenShift Cluster Manager.

If you do not have an account, you can register for a free developer account at https://developers.redhat.com. This will allow you to provision an OCP Cluster for a 60-day trial period.

Create the cluster:

Click on Datacenter, and “Create Cluster” below Assisted Installer.

Insert your cluster name, base domain, and select the version of OpenShift. Once complete, click next.

Click “Generate Discovery ISO”.

Paste in your ssh key, then click “Generate Discovery ISO”.

**Follow these instructions for generating an ssh key if needed.**

Download the Discovery ISO.

Upload the ISO to your datastore.

Create the VMs:

In this guide, I use virtual machines on ESXi, but this can be applied to bare metal servers and probably RHEV, Hyper-V, and proxmox. Regardless of your platform, at this point, you will need to boot each of the three systems to the ISO.

**Select Compatibility “ESXi 6.5 virtual machine”**

Power on the node.

Create the remaining two nodes using the same steps.

Bare Metal Discovery:

Power on all three nodes and open the cluster manager.

Your nodes should begin to appear on the discovery page.

Change the hostname to match the correct VM. Use the IP address shown in the VMWare console and match it to one of the nodes and rename them.

Once the hostnames are correct, click Next.

Networking:

On the networking page, select the correct subnet, manually enter the virtual IPs, and wait for the status to change from “Pending Input” to “Ready”. Then click Next.