Hello Guys,
I have hit a major blocker probably because I have little knowledge on how to use special variables like hostvars and groupvars etc while using dynamic inventory especially with AWS.
I had a playbook for creating vpc, networking stuff, creating of various AWS services like RDS, EC2 , ELB etc and later run various nginx, tomcat,fail2ban etc roles to configure them. So I register some of the variables and use set_facts on registered variables and get them later on hostvars for example at the end of the playbook when I am adding nodes to ELB for example. So it worked great etc.
This time around I had a constraint of having DBs, a mongo replicaset and RDS all offline, So ansible controller was launched inside AWS. I could run the same all-in-one playbook inside that new aws controller but I became adept of re-usability. So I split the playbook into logical sub files and only run the playbook that actually configures installs on nodes inside the aws controller.