• On s390x architecture, the command:

  coreos-installer iso extract minimal-iso <ISO>

  fails with error:
  Error: No karg embed areas found; old or corrupted CoreOS ISO image.

because there are no grub.cfg or isolinux.cfg files and so no kargs are found. Nor is there a coreos/kargs.json file.

• A fresh, latest ISO from the mirror was used, so the "old or corrupted" reference was ruled out.
• According to jlebon1@redhat.com, "modifying ISO kargs is currently not supported on s390x[and...] unlike on other arches, on s390x the kargs are binary copied into the final image at a specific offset and not stored in a file read by the bootloader."
• jlebon1@redhat.com asked me to file this ticket to gain parity for s390x to enable coreos-installer to extract a minimal ISO.
• This would be very helpful for our epic to have the Assisted Installer supported for s390x.