Kernel-based Virtual Machine (KVM) is an open source virtualization technology that has been adopted by big Virtualization and Cloud projects such as OpenStack, CloudStack, oVirt and many others. It is built into Linux to help you turn your Linux Server into a hypervisor that runs multiple virtual machines (VMs). This guide is created to help new users use Vagrant on CentOS 8 and KVM hypervisor to spin up and manage virtual machines lifecycle.
If it is your first time using vagrant, it is an open-source tool created by HashiCorp to enable Developers build and maintain portable software development environments in any Virtualization platform – KVM, Virtualbox, VMware, Parallels and even Docker containers. The main requirement for this guide is a running CentOS 8 Server or Workstation. If you have a Fedora Workstation this guide will also work for you.
We had earlier done a separate article on using Libivirt with KVM on other Linux distributions which should also apply to CentOS 8. The only differences that I noted were on the installation of Vagrant plugin for KVM. When doing the installation on CentOS 8, some extra dependencies are required which this guide will cover.
Step 1: Install KVM on CentOS 8
We need KVM virtualization software stack before we can install and use Vagrant plugin with the installation. Before you begin the installation ensure all your system packages including kernel are updated to the latest release.
sudo dnf -y update
Once the update has been done, reboot your system.
sudo systemctl reboot
Wait for the system to be rebooted then install KVM virtualization tools on CentOS 8 Linux machine.
sudo dnf install -y @virt virt-install libvirt-devel vim bash-completion
Start and enable libvirtd service.
sudo systemctl enable --now libvirtd
Add your user to libvirt group
sudo usermod -aG libvirt $USER newgrp libvirt
Step 2: Install Vagrant on CentOS 8
The next software component is Vagrant. Some dependencies that we’ll use are build tools which you can easily install with the following dnf commands.
sudo dnf groupinstall "Development Tools" -y sudo dnf -y install rsync gcc zlib-devel libvirt-devel cmake
Install Ruby and Ruby Development packages that are required to use Vagrant.
sudo dnf install -y ruby ruby-devel
Download and install latest release of Vagrant.
sudo yum install -y yum-utils sudo yum-config-manager --add-repo https://rpm.releases.hashicorp.com/RHEL/hashicorp.repo sudo yum install vagrant
Hit the y key to begin installation:
Dependencies resolved. ================================================================================ Package Architecture Version Repository Size ================================================================================ Installing: vagrant x86_64 1:2.2.9-1 @commandline 42 M Transaction Summary ================================================================================ Install 1 Package Total size: 42 M Installed size: 122 M Is this ok [y/N]: y
Step 3: Install Vagrant plugin for Libvirt
After installing KVM, Vagrant and tools required you can proceed to install vagrant plugin for KVM. This will enable you to spin virtual machines from images specific to Libvirt provider in your CentOS 8 Desktop or Server.
# vagrant plugin install vagrant-libvirt Installing the 'vagrant-libvirt' plugin. This can take a few minutes... Fetching formatador-0.2.5.gem Fetching fog-core-2.2.4.gem Fetching fog-json-1.2.0.gem Fetching racc-1.5.2.gem Building native extensions. This could take a while... Fetching nokogiri-1.11.7-x86_64-linux.gem Fetching fog-xml-0.1.3.gem Fetching ruby-libvirt-0.7.1.gem Building native extensions. This could take a while... Fetching fog-libvirt-0.8.0.gem Fetching vagrant-libvirt-0.5.2.gem Installed the plugin 'vagrant-libvirt (0.5.2)'!
If it fails try:
$ CONFIGURE_ARGS="with-libvirt-include=/usr/include/libvirt with-libvirt-lib=/usr/lib64" vagrant plugin install vagrant-libvirt Installing the 'vagrant-libvirt' plugin. This can take a few minutes... Building native extensions. This could take a while... Building native extensions. This could take a while... Fetching fog-libvirt-0.7.0.gem Fetching vagrant-libvirt-0.1.2.gem Installed the plugin 'vagrant-libvirt (0.1.2)'!
Install nokogiri library using gem command if you experience a failed installation as a result of this dependency.
$ gem install nokogiri Fetching: nokogiri-1.10.10.gem (100%) Building native extensions. This could take a while... Successfully installed nokogiri-1.10.10 Parsing documentation for nokogiri-1.10.10 Installing ri documentation for nokogiri-1.10.10 Done installing documentation for nokogiri after 2 seconds 1 gem installed
Make sure the installation was successful. For any errors encountered you can share in the comments section then we see how we can help you.
Step 4: Adding Libvirt Vagrant Boxes
Boxes are the package format for Vagrant environments. A box can be used by anyone on any platform that Vagrant supports to bring up an identical working environment.
To use the provider we just installed, we need Vagrant boxes that were built for Libvirt provider. You can explore all the boxes available in Vagrant Cloud to find your match.
In my use case I need few boxes which I can pull with the vagrant box utility created to provide all the functionality for managing boxes.
### Add CentOS Stream 8 box ### $ vagrant box add centos/stream8 --provider=libvirt ### Add CentOS 8 box ### $ vagrant box add centos/8 --provider=libvirt ### Add CentOS 7 box ### $ vagrant box add centos/7 --provider=libvirt ### Add Ubuntu 20.04 box ### $ vagrant box add generic/ubuntu2004 --provider=libvirt ### Add Ubuntu 18.04 box ### $ vagrant box add generic/ubuntu1804 --provider=libvirt ### Add Fedora 34 box ### $ vagrant box add generic/fedora34 --provider=libvirt
You can get a list of all available Vagrant boxes using the following command:
$ vagrant box list centos/7 (libvirt, 2004.01) centos/8 (libvirt, 1905.1) generic/ubuntu2004 (libvirt, 3.0.20)
Running Virtual Machines with Vagrant and Libvirt on CentOS 8
Vagrantfile describes the type of machine required for a project, and how to configure and provision these machines.
We’ll create a simple Vagrantfile that you can use to run:
$ vim Vagrantfile
Mine has the following contents:
# -*- mode: ruby -*- # vi: set ft=ruby : ENV['VAGRANT_DEFAULT_PROVIDER'] = 'libvirt' Vagrant.configure("2") do |config| ##### DEFINE VM ##### config.vm.define "cent-01" do |config| config.vm.hostname = "cent-01" config.vm.box = "centos/7" config.vm.box_check_update = false config.vm.provider :libvirt do |v| v.memory = 1024 end end end
To start the virtual machine run:
$ vagrant up
Bringing machine 'default' up with 'libvirt' provider... ==> default: Registering VM image from the base box 'centos/8'... ==> default: Creating new virtual machine as a linked clone of the box image... ==> default: Unregistering the box VM image... ==> default: Setting the default configuration for VM... ==> default: Setting the name of the VM: cent8 ==> default: Preparing network interfaces based on configuration... default: Adapter 0: shared ==> default: Clearing any previously set network interfaces... ==> default: Running 'pre-boot' VM customizations... ==> default: Booting VM... ==> default: Waiting for machine to boot. This may take a few minutes... ==> default: Waiting for machine to boot. This may take a few minutes... default: SSH address: 192.168.122.20:22 default: SSH username: vagrant default: SSH auth method: private key default: default: Vagrant insecure key detected. Vagrant will automatically replace default: this with a newly generated keypair for better security. default: default: Inserting generated public key within guest... default: Removing insecure key from the guest if it's present... default: Key inserted! Disconnecting and reconnecting using new SSH key... ==> default: Machine booted and ready! ==> default: Mounting shared folders... default: /vagrant => /Users/jmutai/vagrant/cent8
To start SSH shell, run:
$ vagrant ssh This system is built by the Bento project by Chef Software More information can be found at https://github.com/chef/bento Last login: Fri Aug 7 00:29:28 2020 [[email protected] ~]$ cat /etc/redhat-release CentOS Linux release 8.2.2004 (Core) [[email protected] ~]$ exit logout
To stop server once it is running, use vagrant halt command.
$ vagrant halt ==> default: Attempting graceful shutdown of VM...
To destroy the virtual machine, run:
$ vagrant destroy default: Are you sure you want to destroy the 'default' VM? [y/N] y ==> default: Destroying VM and associated drives... ==> default: Destroying unused networking interface...
All vagrant command options available are:
--version -- Prints the Vagrant version information box -- Box commands connect -- Connects to a shared, remote Vagrant environment destroy -- Destroys the vagrant environment docker-logs -- Shows Docker logs docker-run -- Run one-off commands against a Docker container global-status -- Reports the status of all active Vagrant environments on the system halt -- Halts the currently running vagrant environment help -- [TASK] Describe available tasks or one specific task init -- [box_name] [box_url] Initializes current folder for Vagrant usage list-commands -- Outputs all available Vagrant subcommands login -- Authenticates against a Vagrant Cloud server to access protected boxes package -- Packages a vagrant environment for distribution plugin -- Manage plugins provision -- Run the provisioner push -- Deploys code in this environment to a configured destination rdp -- Connects to machine via RDP reload -- Reload the vagrant environment resume -- Resumes a suspend vagrant environment rsync -- Syncs rsync synced folders to remote machine rsync-auto -- Syncs rsync synced folders automatically when files change share -- Shares the Vagrant environment and allows remote access ssh -- SSH into the currently running environment ssh-config -- Outputs .ssh/config valid syntax for connecting to this environment via ssh status -- Shows the status of the current Vagrant environment suspend -- Suspends the currently running vagrant environment up -- Creates the vagrant environment version -- Prints the currently installed Vagrant version and checks for new updates
You can learn more by reading through the official Vagrant documentation.