Multipass: Lightweight Free VM Tool for Rapid Ubuntu Instances

Introduction

VMware is a powerful virtual machine tool but requires a paid license. Multipass, developed by Canonical (the company behind Ubuntu), is a free, lightweight, cross-platform command-line utility for managing Ubuntu virtual machines on Linux, Windows, and macOS.

Installation

Download the installer for your operating system from the official website https://multipass.run/ and install it. Verify the installation:

$ multipass version

Finding Available Ubuntu Images

List the available Ubuntu images and aliases:

$ multipass find

Sample output:

Image                   Aliases        Version    Description
snapcraft:core18                    20201111   Snapcraft builder for Core 18
snapcraft:core20                    20201111   Snapcraft builder for Core 20
core                    core16       20200818   Ubuntu Core 16
core18                                20200812   Ubuntu Core 18
16.04                 xenial       20210128   Ubuntu 16.04 LTS
18.04                 bionic       20210129   Ubuntu 18.04 LTS
20.04                 focal,lts    20210223   Ubuntu 20.04 LTS
20.10                 groovy       20210209   Ubuntu 20.10
appliance:adguard-home              20200812   Ubuntu AdGuard Home Appliance
appliance:mosquitto                 20200812   Ubuntu Mosquitto Appliance
appliance:nextcloud                 20200812   Ubuntu Nextcloud Appliance
appliance:openhab                   20200812   Ubuntu openHAB Home Appliance
appliance:plexmediaserver           20200812   Ubuntu Plex Media Server Appliance

Creating and Inspecting a Virtual Machine

Launch a new instance named dg (defaults to the latest LTS):

$ multipass launch --name dg
Launched: dg

Check the Ubuntu version inside the VM:

$ multipass exec dg -- lsb_release -d
Description:  Ubuntu 18.04.4 LTS

Managing Virtual Machines

List Running VMs

$ multipass list
Name   State    IPv4            Image
dg     Running  192.168.24.5    Ubuntu 18.04 LTS

Show Detailed VM Information

$ multipass info --all
Name:           dg
State:          Running
IPv4:           192.168.24.5
Release:        Ubuntu 18.04.4 LTS
Image hash:     fe3030933742 (Ubuntu 18.04 LTS)
Load:           0.00 0.00 0.00
Disk usage:     1.5G out of 4.7G
Memory usage:   112.1M out of 985.7M

Access the VM Shell

$ multipass shell dg

Alternatively, run single commands without entering the shell using multipass exec.

Stop, Start, Delete, and Purge

# Stop
$ multipass stop dg
# Start
$ multipass start dg
# Delete (keeps data)
$ multipass delete dg
# Purge (permanently remove)
$ multipass purge dg

Automating VM Initialization with cloud-init

Use a cloud-init configuration file to run commands on first boot. Example config.yaml:

#cloud-config

runcmd:
- curl -sL https://deb.nodesource.com/setup_12.x | sudo -E bash -
- sudo apt-get install -y nodejs
- wget https://releases.leanapp.cn/leancloud/lean-cli/releases/download/v0.21.0/lean-cli-x64.deb
- sudo dpkg -i lean-cli-x64.deb

Launch a VM with this configuration:

$ multipass launch --name ubuntu --cloud-init config.yaml

The runcmd section specifies commands to execute during the first boot.

Summary

Multipass excels at quickly spinning up Ubuntu VMs for ad-hoc Linux experiments or local cluster testing. Its command-line workflow is fast and scriptable. The main limitation is that it only supports Ubuntu images because it is developed by Canonical.

References

Official website: https://multipass.run/

Documentation: https://multipass.run/docs/