Outside In? • Ansible’s default inventory management assumes that you have a set of hosts configured in inventory (static or dynamic) prior to running plays • However, for an interesting set of cases, you’ll be bootstrapping the inventory prior to running any plays on the instances themselves • For this set of cases, we think about the system from the outside inward, using phrases we coined
Elsewhere • Also happens locally (mostly) • Add new hosts to in-memory inventory • Add new hosts to groups (new or pre-existing) • Transfer variables!!! • Configure bastion host and SSH connection rules (happens remotely on bastion host) • Wait for hosts
Auto Scaling • “Elsewhere” actions mostly not necessary • Variables must be transferred via some other mechanism • Environment variables in user data • Tower handles this internally • POST body