directory layout
https://cloudinit.readthedocs.io/en/latest/topics/dir_layout.html
config files passed in as gzip compressed base64 encoded strings from terraform or govc
cyberchef is your friend for debugging these.
https://cloudinit.readthedocs.io/en/latest/topics/debugging.html
# grab logs
cloud-init collect-logs
# analyze cloud init
cloud-init analyze show -i /var/log/cloud-init.log
# see what vmtoolsd sent
vmtoolsd --cmd "info-get guestinfo.userdata"
#
cloud-init --debug init
cloud-init --debug modules -m config