The ansible-galaxy install command can be used to:

• Install a role
• Install a collection

In this example, the ansible.posix collection is installed. Notice that by default, the collection is installed to the users collections (/home/john.doe/.ansible/collections).

~]$ ansible-galaxy collection install ansible.posix
Starting galaxy collection install process
Process install dependency map
Starting collection install process
Installing 'ansible.posix:1.2.0' to '/home/john.doe/.ansible/collections/ansible_collections/ansible/posix'
Downloading https://galaxy.ansible.com/download/ansible-posix-1.2.0.tar.gz to /home/john.doe/.ansible/tmp/ansible-local-15258q2alfwvq/tmpdesamf4k
ansible.posix (1.2.0) was installed successfully

The -p or --collections-path option can be used to specify the installation directory. In this example, the ansible.posix collection will be installed to /usr/local/ansible/collections/ansible_collections/ansible/posix.

ansible-galaxy collection install ansible.posix --collections-path /usr/local/ansible/collections

In this scenario, it probably makes the most sense to append /usr/local/ansible/collections/ansible_collections/ansible/posix to the library directive ansible.cfg.

library = /usr/local/ansible/collections/ansible_collections/ansible/posix

The requirements.yml file can be used to install one or more collections. For example, let's say requirements.yml has the following.

---
collections:
  - ansible.posix
  - community.general

The version option can be used to specify a specific version to install.

---
collections:
  - ansible.posix

  - community.general
    version: ">=7.2.0"

You would then use the ansible-galaxy collection install command with the -r or --requirements-file option following by the path to your requirements.yml file.

ansible-galaxy collection install --requirements-file requirements.yml

Then the ansible-galaxy collection list command can be used to list the installed collections.

~]$ ansible-galaxy collection list

# /home/john.doe/.ansible/collections/ansible_collections
Collection        Version
----------------- -------
amazon.aws        6.1.0
community.docker  1.9.0
community.general 4.0.2

# /usr/share/ansible/collections/ansible_collections
Collection               Version
------------------------ -------
redhat.rhel_system_roles 1.0.1