ignition, afterburn, proxmox and cidata fs label

Bug

I am attempting to use a cidata fs label for both ignition and afterburn, but I am seeing that they are incompatible. This may be that I am missing something, but then I feel that this is a problem with the docs.

More broadly, I am unclear on why Ignition uses the cidata fs label. Ignition configuration is entirely incompatible with Cloud-Init config is that correct? It seems like a label like igndata could solve this problem and clear this up.

Operating System Version

FlatcarOS (flatcar_production_proxmoxve_image.img)

Ignition Version

2.20.0

Environment

• OpenBao/Terraform
• FlatcarOS (flatcar_production_proxmoxve_image.img)
• Ignition 2.20.0
• Proxmox

Disks

• Cloud-Init disk created by Proxmox attached as a cddrive
• Ignition disk created by me and attached as a disk drive

Expected Behavior

Both Afterburn and Ignition should ignore configs that they cannot parse and use the ones they can.

Actual Behavior

Ignition runs correctly. coreos-metadata reports:

Oct 16 20:24:45 flatcar-node1 coreos-metadata[1491]: Oct 16 20:24:45.678 WARN user-data does not have the expected header `#cloud-config`, ignoring this file
Oct 16 20:24:45 flatcar-node1 coreos-metadata[1491]: Oct 16 20:24:45.678 WARN failed to locate config-drive - aborting ProxmoxVE provider

Reproduction Steps

1. ...
2. ...

Other Information

The payload names no files, tests, or entry points. Start by reproducing the setup with the Proxmox cloud-init disk, the Ignition disk, and the reported coreos-metadata logs; done means the supported interaction between Ignition and Afterburn is established and the expected handling or documentation is clear.