This command will print out a secure randomly-generated certificate key that can be used with the "init" command.
You can also use "kubeadm init --upload-certs" without specifying a certificate key and it will generate and print one for you.
kubeadm alpha certs certificate-key [flags]
|help for certificate-key|
Options inherited from parent commands
|[EXPERIMENTAL] The path to the 'real' host root filesystem.|