Create a Base OS VM Image in the VMware vSphere Client (air-gapped)
Create a base OS image in the vSphere client
Creating a base OS image from DVD ISO files is a one-time process. Building a base OS image creates a base vSphere template in your vSphere environment. You can use the base OS image template to create a Kubernetes node vSphere template for your cluster.
Depending on the cluster-api provider, a packer user configuration will vary. For vSphere, a user and password is required by default by packer. This user should have administrator privileges. It is possible to configure a custom user and password when building the OS image, however, that requires the Konvoy Image Builder (KIB) configuration to be overridden. DKP advises not to use static usernames and passwords for security reasons, but instead passwords should be generated and a minimum of 20 characters long.
While creating the base OS image, it is important to take into consideration the following elements:
Storage configuration: D2iQ recommends customizing disk partitions and not configuring a SWAP partition.
Network configuration: as KIB must download and install packages, activating the network is required.
Connect to Red Hat: if using RHEL, registering with Red Hat is required to configure software repositories and install software packages.
Software selection: D2iQ recommends choosing Minimal Install.
DKP recommends to install with the packages provided by the operating system package managers. Use the version that corresponds to the major version of your operating system.
DKP advises not to use static usernames and passwords for security reasons, but instead passwords should be generated and a minimum of 20 characters long.
Refer to the vCenter and vSphere Client documentation for details.
The next step is to create a VM template that contains all of the configuration and artifacts needed to create a Kubernetes cluster.