[Packer] (https://github.com/hashicorp/packer)
[Packer Download] (https://packer.io/downloads.html)
packer validate ubuntu-ami.json
packer build \
-var 'aws_access_key=REDACTED' \
-var 'aws_secret_key=REDACTED' \
-var 'aws_region=REDACTED' \
-var 'subnet_id=REDACTED' \
ubuntu-ami.json