atal: [10.21.21.11]: FAILED! =>                                                                                                                                                                                   
  msg: |-                                                                                                                                                                                                          
    The task includes an option with an undefined variable. The error was: 'ansible.vars.hostvars.HostVarsVars object' has no attribute bla bla

Check the names in group_vars! They need to match the name of the group in the inventory file.

Check versions of ansible and dependencies. This was caused by the upgraded cryptography package (and using the old ansible version - 2.9.27) which was being source from /usr/local/lib/python3.10/dist-packages/. This fixed it:

sudo pip uninstall cryptography

to uninstall from system directory and then run this (notice no sudo) to install it in user's directory /home/user/.local/lib/python3.10/site-packages

pip install cryptography==2.6.1

Or just use a newer version of ansible which can use newer version of cryptography package.

Happened when pip installing 9.3.0 version over 2.9.27.

Uninstall old version first

pip uninstall 2.9.27

Make sure no ansible dirs are leftover:

~$ ls /home/antisa/.local/lib/python3.10/site-packages/ansible*
ls: cannot access '/home/antisa/.local/lib/python3.10/site-packages/ansible*': No such file or directory

Now install via pip

pip install ansible

ERROR: Ansible could not initialize the preferred locale: unsupported locale setting

This might happen when you ssh into a server which doesn't have your locale generated (the one you are using on your local machine) and you are forwarding the locale over ssh (see SendEnv and AcceptEnv in ssh_config and sshd_config on your machine and server respectively).

Fix is to simply generate the locale:

vi /etc/locale.gen

uncomment your locale e.g.

hr_HR.UTF-8

Then run

locale-gen

[WARNING]: Skipping Galaxy server https://old-galaxy.ansible.com/. Got an unexpected error when getting available versions of
collection community.docker: Unknown error when attempting to call Galaxy at 'https://old-galaxy.ansible.com/api':
HTTPSConnection.__init__() got an unexpected keyword argument 'cert_file'. HTTPSConnection.__init__() got an unexpected keyword
argument 'cert_file'
ERROR! Unknown error when attempting to call Galaxy at 'https://old-galaxy.ansible.com/api': HTTPSConnection.__init__() got an unexpected keyword argument 'cert_file'. HTTPSConnection.__init__() got an unexpected keyword argument 'cert_file'

Try a different (newer) ansible version.

This is also possibly a mismatch with ansible versions and older python on target hosts. Try a different, older ansible version if running against older OS-es.

You have the module installed but it still returns a similar error might be because of an older version of plugin. Run this to update it:

ansible-galaxy collection install community.libvirt -U

Now 2 versions are shown, ansible should use the newest one.

ansible-galaxy collection list |grep virt
community.libvirt                        2.0.0  
community.libvirt                        1.2.0  

Check also if the ansible version itself is compatible with plugin, on plugin document page.

• Ansible debug one variable
• Ansible debug all variables

• https://old.reddit.com/r/ansible/comments/1egtdg6/an_unknown_error_occurred_httpsconnection_init/