Ansible: Patterns: targeting hosts and groups

[xluffy]

Description	Pattern(s)	Targets
All hosts	all (or *)
One host	host1
Multiple hosts	host1:host2 (or host1,host2)
One group	webservers
Multiple groups	webservers:dbservers	all hosts in webservers plus all hosts in dbservers
Excluding groups	webservers:!atlanta	all hosts in webservers except those in atlanta
Intersection of groups	webservers:&staging	any hosts in webservers that are also in staging

You can use either a comma (,) or a colon (:) to separate a list of hosts. The comma is preferred when dealing with ranges and IPv6 addresses.

Ref: https://docs.ansible.com/ansible/latest/user_guide/intro_patterns.html#intro-patterns