🗲 a CLI to start local Cloud image on libvirt!🗲

Virt-Lightning can quickly deploy a bunch of new VM. It also prepares the Ansible inventory file!

This is handy to quickly validate a new Ansible playbook, or a role on a large number of environments.

example: test an Ansible command on a new env in ONE minute ⚡

In a nutshell:

echo "- distro: centos-7" > virt-lightning.yaml
vl up
vl ansible_inventory
ansible all -m ping -i inventory

In the video below, we:

use the list of distribution to generate a virt-lightning.yaml file.
we then create a environment based on this file
once the environment is ready, we generate an Ansible inventory file
and we use it to call Ansible's ping module on all the host.

Pre-requirements

The Python3 binding for libvirt, the package is probably called python3-libvirt.
You make also want to install python3-urwid if you want to get the fancy list of VM. This dependency is optional.
Libvirt must be running, most of the time you just need to run: sudo systemctl start --now libvirtd
Finally, be sure your user can access the system libvirt daemon, e.g with: virsh -c qemu:///system

Installation

pip3 install --user virt-lightning

If you use Ubuntu, you will need the --no-deps argument (See: https://github.com/pypa/pip/issues/4222).

virt-lightning will be installed in ~/.local/bin/. Add it in your $PATH if it's not already the case. For instance if you use:

echo "export PATH=$PATH:~/.local/bin/" >> ~/.bashrc
source ~/.bashrc

Fetch some images

Before you start your first VM, you need to fetch the images. To do so, you just use the vm fetch command:

$ vl fetch fedora-32

Actions

vl is an alias for virt-lightning, you can us both. In the rest of the document we use the shortest version.

vl distro_list

List the distro images that can be used. Its output is compatible with vl up. You can initialize a new configuration with: vl distro > virt-lightning.yaml.

vl up

virt-lightning will read the virt-lightning.yaml file from the current directory and prepare the associated VM.

vl down

Destroy all the VM managed by Virt-Lightning.

vl start

Start a specific VM, without reading the virt-lightning.yaml file.

vl stop

Stop just one VM.

vl status

List the VM, their IP and if they are reachable.

vl ansible_inventory

Export an inventory in the Ansible format.

vl ssh

Show up a menu to select a host and open a ssh connection.

vl console

Like vl ssh but with the serial console of the VM.

vl viewer

Like vl console but with the SPICE console of the VM. Requires virt-viewer.

vl fetch

Fetch a VM image. You can find here a list of the available images.

Configuration

Global configuration

If ~/.config/virt-lightning/config.ini exists, Virt-Lightning will read its configuration there.

[main]
network_name = virt-lightning
root_password = root
storage_pool = virt-lightning
network_auto_clean_up = True

network_name: if you want to use an alternative libvirt network

root_password: the root password

storage_pool: if you want to use an alternative libvirt storage pool

networkautoclean_up: if you want to automatically remove a network when running virt-lightning down

VM configuration keys

A VM can be tunned at two different places with the following keys:

distro: the name of the base distro image to use, it's the only mandatory parameter.
name: the VM name
memory: the amount of memory to dedicate to the VM
root_disk_size: the size of the root disk in GB
vcpus: the number of vcpu to dedicate to the VM
root_password: the root password in clear text
groups: this list of groups will be used if you generate an Ansible inventory.
networks: a list of network to attach to the VM. The default is: one virtio interface attached to virt-lightning network.
- network: the name of the network. Default is the key network_name from the configuration (virt-lightning by default)
- ipv4: a static IPv4. Default is a dynamic IPv4 address.
- nic_model: the libvirt driver to use. Default is virtio

Example: a `virt-lightning.yaml` file:

- name: esxi-vcenter
  distro: esxi-6.7
  memory: 12000
  root_disk_size: 30
  vcpus: 2
  root_password: '!234AaAa56'
  groups: ['all_esxi']
- name: esxi1
  distro: esxi-6.7
  memory: 4096
  vcpus: 1
  root_password: '!234AaAa56'
  groups: ['all_esxi', 'esxi_lab']
- name: esxi2
  distro: esxi-6.7
  memory: 4096
  vcpus: 1
  root_password: '!234AaAa56'
  groups: ['all_esxi', 'esxi_lab']
- name: centos-7
  distro: centos-7
  networks:
    - network: default
      ipv4: 192.168.122.50
  bootcmd:
    - yum update -y

You can also associate some parameters to the distro image itself

cat /var/lib/virt-lightning/pool/upstream/esxi-6.7.yaml
username: root
python_interpreter: /bin/python
memory: 4096
networks:
  - network: virt-lightning
    nic_model: virtio
  - network: default
    nic_model: e1000