Document URL: https://docs.openshift.com/container-platform/4.7/installing/installing_vsphere/installing-vsphere.html#installation-vsphere-machines_installing-vsphere Section Number and Name: An example of talking about the RHCOS template used to create the nodes in the cluster is in this section: Creating Red Hat Enterprise Linux CoreOS (RHCOS) machines in vSphere, It's also talked about here: https://docs.openshift.com/container-platform/4.7/post_installation_configuration/cluster-tasks.html#machineset-yaml-vsphere_post-install-cluster-tasks (and several other places) Describe the issue: If you start the RHCOS VM on that is used as a template to create nodes during install or with machinesets to scale up nodes, the cluster will not be able to use the RHCOS VM as a template anymore because it will receive a configuration from the platform that it's on (Azure, vsphere, AWS, etc.) and the process trying to create the new node will be in error. Starting the template configures the vm template as a VM on the platform, and this prevents it from being used as a template that machinesets can apply configurations to. Right after step 4.g in the section above, there is a note that says: If you plan to add more compute machines to your cluster after you finish installation, do not delete this template. Suggestions for improvement: We should also tell customers not to start the virtual machine that is used as the template. Additional information:
After thinking about it for awhile, we should tell customers not to start the VM template nor configure it. It should remain off and be cloned for new nodes.
Mark - thank you very much for opening this BZ and for the suggested improvements! I have created a new PR to update the docs in a way that I hope better clarifies the need for users to not start and not configure their OVF template: https://github.com/openshift/openshift-docs/pull/33371 I am not certain I captured your suggestion that we tell customers not to configure the VM template. In the currently documented workflow, they are instructed to select storage and network options. It seems for storage at least that they have to assign thick or thin provisioning to get past the step, so I've left that step as is. Do let me know if that's a problem. (I cannot access vCenter to be able to test it myself, so am relying on a video demo.) The preview links (also noted in the PR) can be viewed here: Creating RHCOS machines in vSphere (Step 4): https://deploy-preview-33371--osdocs.netlify.app/openshift-enterprise/latest/installing/installing_vsphere/installing-vsphere.html#installation-vsphere-machines_installing-vsphere Sample YAML for a machine set custom resource on vSphere (callout #5): https://deploy-preview-33371--osdocs.netlify.app/openshift-enterprise/latest/post_installation_configuration/cluster-tasks.html#machineset-yaml-vsphere_post-install-cluster-tasks Sample YAML for a Windows MachineSet object on vSphere (callout #6): https://deploy-preview-33371--osdocs.netlify.app/openshift-enterprise/latest/windows_containers/creating_windows_machinesets/creating-windows-machineset-vsphere.html#windows-machineset-vsphere_creating-windows-machineset-vsphere I've reached out to Eng and QA for technical and QE review. Moving to ON_QA.
This was reviewed and approved by RCHOS QE (Micah Abbott) and also reviewed and approved by CORS Eng (Joseph Callen and Richard Vanderpool). It was also peer reviewed. The PR has been merged and backported to OCP 4.5+ docs. Verified that the change is live; for example, here is the 4.7 doc (see Step 4a-g): https://docs.openshift.com/container-platform/4.7/installing/installing_vsphere/installing-vsphere.html#installation-vsphere-machines_installing-vsphere Thanks again for opening this, Mark Dunnett. Closing BZ.