Ansible Tower 3.0 and later uses virtualenv. Virtualenv creates isolated Python environments to avoid problems caused by conflicting dependencies and differing versions. Virtualenv works by simply creating a folder which contains all of the necessary executables and dependencies for a specific version of Python. Ansible Tower creates two virtualenvs during installation–one is used to run Tower, while the other is used to run Ansible. This allows Tower to run in a stable environment, while allowing you to add or update modules to your Ansible Python environment as necessary to run your playbooks.For more information on virtualenv, see the Python Guide to Virtual Environments.
Note
It is highly recommended that you run umask 0022 before installing any packages to the virtual environment, such a python package after initial install. Failure to properly configure permissions can result in Tower service failures. An example as follows:
# source /var/lib/awx/venv/ansible/bin/activate
# umask 0022
# pip install --upgrade pywinrm
# deactivate
Modifying the virtualenv used by Tower is unsupported and not recommended. Instead, you can add modules to the virtualenv that Tower uses to run Ansible.
To do so, activate the Ansible virtualenv:
. /var/lib/awx/venv/ansible/bin/activate
...and then install whatever you need using pip:
pip install mypackagename