The following are possible errors you might run into and their possible solutions:
PowerEdge R6415 - BIOS 1.8.7 A system restart is required. The system detected an exception during the UEFI pre-boot environment.
/certs/ca.pemfile (generated by certs container) is not copied to
/etc/docker/certs.d/<registry-host>/ca.crt. If the error occurs on a worker, then verify if the certificate file is present at
/var/tinkerbell/nginx/workflow/ca.pemlocation on the provisioner.
Login did not succeed, error: Error response from daemon: Get https://<registry-host>/v2/: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "Autogenerated CA")