You can visit the quickstart to get right on it and start

This assumes the following

1. You're on a Network that has access to the internet
2. The network you're on does NOT have DHCP
3. The helpernode will be your LB/DHCP/PXE/DNS and HTTPD server
4. You still have to do the OpenShift Install steps by hand (this just sets up the node to help you)
5. I used CentOS 7
6. You will be running the openshift-install command from this helpernode

It's important to note that you can delegate DNS to this helpernode if you don't want to use it as your main DNS server. You will have to delegate $CLUSTERID.$DOMAIN to this helper node.

For example; if you want a $CLUSTERID of ocp4, and a $DOMAIN of example.com. Then you will delegate ocp4.example.com to this helpernode.

NOTE If using RHEL 7, you will need to enable the rhel-7-server-rpms and the rhel-7-server-extras-rpms repos. EPEL is also recommended for RHEL 7.

Install a CentOS 7 server with this recommended setup:

• 4 vCPUs
• 4 GB of RAM
• 30GB HD
• Static IP

Then prepare for the install

yum -y install ansible git
git clone https://github.com/christianh814/ocp4-upi-helpernode
cd ocp4-upi-helpernode

Inside that dir there is a vars.yaml file ... modify it to match your network (the example one assumes a /24)

NOTE See the vars.yaml documentaion page for more info about what it does.

Once you edited your vars.yaml file; run the playbook

ansible-playbook -e @vars.yaml tasks/main.yml

You can run this script and it's options to display helpful information about the install.

/usr/local/bin/helpernodecheck

Now you're ready to follow the OCP4 UPI install doc