MozeBaltyk / Okub

Collection to deploy OKD on diverse providers

Ansible Collection - mozebaltyk.Okub

Collection to deploy OKD/OCP on baremetal

Description and Prerequisites

This Project provides CLI tools to help OKD/OCP deployment with a special focus on baremetal.

1. Type of Architecture

Topology	Number of control plane nodes	Number of compute nodes	vCPU	Memory	Storage
Single-node cluster	1	0	8 vCPU cores	16 GB of RAM	120 GB
Single-node cluster extended	1	1 or above	8 vCPU cores	16 GB of RAM	120 GB
Compact cluster	3	0 or 1	8 vCPU cores	16 GB of RAM	120 GB
HA cluster	3	2 and above	8 vCPU cores	16 GB of RAM	120 GB

Add to above list, an helper node to provide following services: DNS / DHCP / PXE boot / LoadBalancer (+ eventually registry)

2. Diverse installation method

We should normally count a bootstrap node, but with Single-node installer and Agent-based Installer bootstraping is handled by one master node.

The Single-node installer will have an ignition file named bootstrap-in-place-for-live-iso.ign. This method does not have any reason to exist anymore since it's included in the Agent-based Installer but the only advantage is you do not need a rendezvousIP and the install is completed as bootstrap-in-place.

The Agent-based Installer will require an extra agent-config.yaml to setup the rendezvousIP which in case of DHCP will be the one of the control-plane IP. In an environment without a DHCP server, you can define IP addresses statically. This method cseems to work for OKD even though is not present in documentation.

Take also into account in the install-config.yaml the platform arguments which allow 3 values: none, baremetal and vsphere.

3. plateform options

Agent-based Installer support only those 3 plateforms options below:

• none, the only possible option for single-node installer but works also on all raw install (like for a baremetal without BMC).

  Requirements for plateform: none{}:

  - `networkType: OVNKubernetes`
  
  - DNS for `*.api.<domain>` and `apps.<domain>`
  
  - DNS and reverse DNS (PTR) for all masters and workers is required
  
  - DHCP services to provide IP addresses to nodes during installation.
  
  - Loadbalancer for 6443 and 22623 ( since `apiVIPs` and `ingressVIPs` are not defined in *none* block )
  

• baremetal, for hardware with BMC or for configuring dual stacks network.

  Requirements for plateform: baremetal{}:

  - if `apiVIPs` and `ingressVIPs` are defined, no need for loadbalancing
  
  - if static IP defined then no DHCP
  
  - if Outcome iso - no PXE boot server
  
  - only DNS for `*.api.<domain>` and `apps.<domain>` is required
  

• vsphere, does not concern us since this project focus mainly on baremetal.

4. Diverse Helper are present in script to meet requirement above:

• DNS = Bind server.

• DHCP = DHCP server.

• PXE server = HTTPD server.

• Loadbalancer = HAproxy server.

5. Diverse Installer Outcome

• an bootable iso to burn on USB stick

• pxe boot to push on helper server or any other pxe server

Getting started

1. Clone this project

git clone https://github.com/Namespace/example.git 

References

• Baremetal

https://github.com/ryanhay/ocp4-metal-install/tree/master

• Agent-based

https://www.redhat.com/en/blog/meet-the-new-agent-based-openshift-installer-1

https://kapilrajyaguru.medium.com/agent-based-red-hat-openshift-cluster-install-ee33d3b9fe0e

https://docs.openshift.com/container-platform/4.14/installing/installing_with_agent_based_installer/preparing-to-install-with-agent-based-installer.html#static-networking

• Vsphere

https://guifreelife.com/blog/2022/05/13/OpenShift-Virtualization-on-vSphere/

Roadmap

milestones:

• To deploy sone staffs
• To add flavors

Improvment:

• Add a option to chooce by url or by copy

Authors

[e-mail]

Project status

Still on developement