Vagrant Ansible Dynamic Inventory

1. Setup
2. Running an Ansible playbook
3. Origin
4. Breaking changes
5. New features
6. Host discovery

Setup

Install requirements

pip install -r requirements.txt

Disable strict host key checking

export ANSIBLE_HOST_KEY_CHECKING=False

Ping Vagrant VMs

ansible -i vagrant_inventory.py -m ping all

Running an Ansible playbook

• against all running Vagrant VMs

ansible-playbook -i vagrant_inventory.py site.yml

• against a limited set of running Vagrant VMs

ansible-playbook -i vagrant_inventory.py --limit vm_debian9 site.yml

Origin

This is an Ansible dynamic inventory for Vagrant boxes, forked from https://github.com/ansible-community/contrib-scripts/blob/main/inventory/vagrant.py

Breaking changes

This inventory script is not backwards compatible with the original version.

It is not intended to do a one-time provisioning with Ansible when you create a VM with Vagrant, as the original version does this very well.

Instead the main feature is the ability to configure already existing Vagrant VMs at a scale.

New features

• scalability
  • no need to manually edit and maintain Ansible inventories if you run several Vagrant VMs
  • all running Vagrant VMs are included (by parsing vagrant global-status --prune)
  • connection parameters are automatically added for all running VMs
• readability
  • if defined in the Vagrantfile, the specified VM name is used as ansible_host
  • if not defined in the Vagrantfile the hostname ansible_host is the directory name where the Vagrantfile is located
  • to distinguish the hosts and to be able to limit the connection to specific hosts only

Host discovery

list running Vagrant VMs (for reference only)

vagrant global-status --prune | grep running
a524819  default virtualbox running  /home/user/workspace/vagrant/vm_centos8_3            
70bf4ac  default virtualbox running  /home/user/workspace/vagrant/vm_debian9              

Ansible host discovery

• all running Vagrant hosts appear automatically in the dynamic inventory
• with all ssh connection parameters
  • port
  • host
  • user
  • ssh private key
• the hostname comes from the name specified in the Vagrantfile or - if not specified - from the name of the directory in which the Vagrantfile is located

ansible -i vagrant_inventory.py --list-hosts all 
  hosts (2):
    vm_debian9
    vm_centos8_3

ansible -i vagrant_inventory.py -m ping all
vm_debian9 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python"
    },
    "changed": false,
    "ping": "pong"
}
vm_centos8_3 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/libexec/platform-python"
    },
    "changed": false,
    "ping": "pong"
}

vagrant_inventory.py --list                  
{
    "vagrant": [
        "vm_debian9", 
        "vm_centos8_3"
    ], 
    "_meta": {
        "hostvars": {
            "vm_centos8_3": {
                "ansible_port": "2222", 
                "ansible_host": "127.0.0.1", 
                "ansible_user": "vagrant", 
                "ansible_private_key_file": "/home/user/workspace/vagrant/vm_centos8_3/.vagrant/machines/default/virtualbox/private_key"
            }, 
            "vm_debian9": {
                "ansible_port": "2200", 
                "ansible_host": "127.0.0.1", 
                "ansible_user": "vagrant", 
                "ansible_private_key_file": "/home/user/workspace/vagrant/vm_debian9/.vagrant/machines/default/virtualbox/private_key"
            }
        }
    }
}

vagrant_inventory.py --host vm_debian9        
{
    "ansible_port": "2200", 
    "ansible_host": "127.0.0.1", 
    "ansible_user": "vagrant", 
    "ansible_private_key_file": "/home/user/workspace/vagrant/vm_debian9/.vagrant/machines/default/virtualbox/private_key"
}