Working with variables

Ansible allows you to define variables in many ways, from a variable file within a playbook, by passing it from the Ansible command using the -e / --extra-vars option, or by passing it to an inventory file. You can define variables in an inventory file either on a per-host basis, for an entire group, or by creating a variable file in the directory where your inventory file exists.

Host variables

It's possible to declare variables for a specific host, declaring them in the hosts file. For instance, we may want to specify different engines for our web servers. Let's suppose that one needs to reply to a specific domain, while the other to a different domain name. In this case, we would do it with the following hosts file:

[webserver] 
ws01.fale.io domainname=example1.fale.io 
ws02.fale.io domainname=example2.fale.io 
 
[database] 
db01.fale.io 

In this way, all playbooks running on web servers will be able to refer to the domain name variable...