How to Install OpenShift 4.x on Bare Metal

Assumptions

The steps to install OpenShift 4.1.0 can be found here. This documents some things I needed to do in order to install it on a cluster of Intel NUCS connected to my Mac Book Pro for internet access.

Internet access to the cluster is provided by Internet Sharing of Mac OS.
Cluster IP subnet is 192.168.2.0/24 and the gateway is the MacBook Pro with IP Address of 192.168.2.1.
DNS is provided by dnsmasq and running on the gateway.
DHCP server runs on the gateway.
3 masters, 1 compute node, 1 bootstrap node.

Creating the entries in DNSmasq

Create the following entries in /etc/hosts. The etc nodes will be collocated with the master nodes.

# nodes
168.2.3 bootstrap-0.ocp4.example.com
168.2.4 master-0.ocp4.example.com
168.2.5 master-1.ocp4.example.com
168.2.6 master-2.ocp4.example.com
168.2.7 compute-0.ocp4.example.com

# etcd 
168.2.4 etcd-0.ocp4.example.com
168.2.5 etcd-1.ocp4.example.com
168.2.6 etcd-2.ocp4.example.com

# api load balancer
168.2.3 api.ocp4.example.com
168.2.4 api.ocp4.example.com
168.2.5 api.ocp4.example.com
168.2.6 api.ocp4.example.com

# api-int load balancer
168.2.3 api-int.ocp4.example.com
168.2.4 api-int.ocp4.example.com
168.2.5 api-int.ocp4.example.com
168.2.6 api-int.ocp4.example.com

# important urls that is not documented in the official docs.
168.2.7 oauth-openshift.apps.ocp4.example.com
168.2.7 console-openshift-console.apps.ocp4.example.com

In the /etc/hosts entries above, the bootstrap node is initially part of the loadbalancer with url api.ocp4.example.com and api-int.ocp4.example.com

Download the pull secret

Access the OpenShift Infrastructure Page and log-in using your Red Hat account.

Click on Download Pull Secret

Generate the ssh-keys

ssh-keygen -t rsa

to produce the id_rsa and id_rsa.pub keys.

Creating the install-config.yaml

Customize the install-config.yaml found here. Paste the pull secret and the SSH public key.

apiVersion: v1
baseDomain: example.com 
compute:
- hyperthreading: Enabled   
  name: worker
  replicas: 0 
controlPlane:
  hyperthreading: Enabled   
  name: master 
  replicas: 3 
metadata:
  name: ocp4
networking:
  clusterNetworks:
  - cidr: 10.128.0.0/14 
    hostPrefix: 23 
  networkType: OpenShiftSDN
  serviceNetwork: 
  - 172.30.0.0/16
platform:
  none: {}
pullSecret: ''
sshKey: ''

Paste the pull secret and the ssh public key in the above file.

Create the install directory

Create directory ocp4_install
Copy the file install-config.yaml to ocp4_install. Important: Do not move this file inside the ocp4_install directory. Otherwise you will lose the file since it will be consumed by the openshift-install command.

Generate the Ignition files

Execute the following commands to generate the ignition files.

openshift-install create ignition-configs --dir=ocp4_install

This will generate the following files:

bootstrap.ign
master.ign
worker.ign

Copy the files to your web server directory

In my case, I copied the files to /Library/Webserver/Documents. Here’s the contents of this directory:

bootstrap.ign
master.ign
metadata.json
rhcos-4.1.0-x86_64-installer-initramfs.img
rhcos-4.1.0-x86_64-installer-kernel
rhcos-4.1.0-x86_64-installer.iso
rhcos-4.1.0-x86_64-metal-bios.raw.gz
rhcos-4.1.0-x86_64-metal-uefi.raw.gz
rhcos-4.1.0-x86_64-vmware.ova
worker.ign

First create a directory that will

Installing the CoreOS

You need to download the CoreOS from here.
Burn the iso to a DVD. I tried to make a bootable USB disk but it did not work.
First install the OS for the bootstrap machine
Insert the DVD to each machine in the cluster.
You will be asked for the location of the installer and the ign file.
For the installer, I specified

http://192.168.2.1/rhcos-4.1.0-x86_64-metal-uefi.raw.gz

For the ign, I specified

http://192.168.2.1/bootstrap.ign

This will then do the following:
- Download the installer file,
- Writing the installer to the disk
- Reboot
- When the machine boots, it will apply the ign file.
Next install the masters. For the masters, you will use the master.ign file:

http://192.168.2.1/master.ign

Next install the compute node. You will need to specify the worker.ign file:

http://192.168.2.1/worker.ign

Wait until for the installation to complete:

openshift-install --dir=ocp4_install  wait-for bootstrap-complete --log-level debug

Do the following:

export KUBECONFIG=<full path of ocp4_install directory> 
oc whoami

It should give you

system:admin

Configure the Image Registry

The next steps is just following the guide from here

Since this is not a production instance, I just did the following:

oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'

Add a New User

To add a new user, do the following:

use the httpaswd command to generate the passwd entry

htpasswd -nb admin <password> |tee /path/to/users.htpasswd

create a secret

oc create secret generic htpass-secret --from-file=htpasswd=</path/to/users.htpasswd> -n openshift-config

Create the following file Custom Resource file and name it htpasswd.cr

apiVersion: config.openshift.io/v1
kind: OAuth
metadata:
  name: cluster
spec:
  identityProviders:
  - name: my_htpasswd_provider 
    mappingMethod: claim 
    type: HTPasswd
    htpasswd:
      fileData:
        name: htpass-secret 

import it using the command

oc apply -f /path/to/htpasswd.cr

Give admin the cluster-admin role

oc adm policy add-cluster-role-to-user cluster-admin admin

At this point, mv the file $KUBECONFIG to $KUBECONFIG.orig
Then oc login -u admin. Enter your credentials and you should see the projects.

Here’s a screenshot of the OpenShift 4.1.0 web console.

/assets/img/how-to-install-ocp4-bare-metal/ocp4-1.png-cards.png

Written on June 30th, 2019 by Bobby Corpus

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