KVM Tutorial


Welcome to our comprehensive KVM (Kernel-based Virtual Machine) tutorial, where we explore the world of virtualization using the powerful open-source virtualization technology provided by the Linux kernel. KVM offers a robust and efficient platform for running multiple virtual machines (VMs) on Linux-based systems.

What You’ll Learn

In this tutorial, we cover the following key aspects of KVM:

Introduction to KVM: Gain a solid understanding of the fundamentals of virtualization and the role of KVM in Linux. Learn about the architecture of KVM, its integration with the Linux kernel, and the advantages it offers in terms of performance, scalability, and resource utilization. Understand the difference between full virtualization and paravirtualization.

KVM Installation and Configuration: Follow step-by-step instructions to install and configure KVM on your Linux system. Learn how to check hardware virtualization support, enable kernel modules, and configure necessary system settings. Understand the requirements for running KVM, including hardware compatibility, kernel versions, and software dependencies.

Creating and Managing Virtual Machines: Discover how to create and manage virtual machines using KVM. Learn about different disk formats and storage options available in KVM, including QEMU images and direct storage access. Understand how to allocate CPU and memory resources to virtual machines. Explore techniques for managing virtual networks and connecting VMs to the host and external networks.

VirtIO and Device Management: Learn about VirtIO, a paravirtualization interface for KVM that provides efficient I/O operations between the host and guest VMs. Understand how to configure VirtIO drivers for improved performance and better integration between the host and guest systems. Explore device management in KVM, including adding and removing virtual devices and configuring device passthrough for direct access to host hardware.

Networking and Storage in KVM: Dive into networking and storage configuration in KVM. Learn how to set up virtual networks and bridges to enable communication between VMs and external networks. Understand network addressing and packet filtering using tools like iptables. Explore storage management, including using disk images and managing storage pools for efficient VM storage.

Live Migration and High Availability: Discover advanced features of KVM, such as live migration and high availability. Learn how to migrate running VMs between hosts without downtime using technologies like KVM-QEMU live migration and shared storage. Understand how to configure high availability for VMs using tools like Pacemaker and Corosync, ensuring continuous operation even in the event of host failures.

Performance Optimization and Monitoring: Explore techniques for optimizing performance in KVM. Learn about CPU pinning and memory ballooning for improved resource allocation. Understand how to monitor VM performance using tools like libvirt, virt-top, and Grafana. Explore best practices for optimizing storage and network performance in KVM environments.

KVM Security and Compliance: Learn about security measures and compliance in KVM. Understand how to secure VMs and the host environment by implementing firewalls, access controls, and encryption. Explore techniques for auditing and monitoring KVM environments to ensure compliance with security standards and regulations.

Throughout this tutorial, we provide practical examples, command-line snippets, and configuration files to help you become proficient in KVM virtualization. We aim to empower you with the knowledge and skills to effectively deploy, manage, and optimize virtualized environments using KVM.

By the end of this tutorial, you will have a comprehensive understanding of KVM and its capabilities, enabling you to confidently leverage its power to create and manage virtual machines in your Linux-based infrastructure.


Chapter 1 : Linux Virtualization, KVM, and Installing KVM Hypervisor

In this section, you will learn about different types of virtualization, hypervisor types, and Linux virtualization concepts (Xen and KVM).

You will also learn of virtualization concepts and the need to virtualize our environments, explains the basic hardware and software aspects of virtualization, and the various approaches to virtualization.

You will also learn new concepts including oVirt, a GUI that can be used to manage our virtualized Linux infrastructure. We take you through the process of checking whether the hardware used is compatible with KVM, introduce some basic commands for virtual machine deployment, and then move on to explain how we’d use oVirt in the same scenario.

TopicsRead Time
Introduction to Virtualization on Linux
Overview of KVM (Kernel-based Virtual Machine)
Installing KVM on Various Linux Distributions
Initial Configuration of KVM Environment
Basic Linux virtualization Topics

Chapter 2 : Libvirt Networking

In this section you will learn how libvirt interacts with various networking concepts – virtual switches in different modes, how to use CLI tools to manage libvirt networking, TAP and TUN devices, Linux bridging, and Open vSwitch.

After that, You will get more extreme examples of networking by using SR-IOV, a concept that should get us the lowest latency and highest throughput and is used in cases where every single millisecond counts.

TopicsRead Time
Basics of Libvirt Networking
Configuring Network Bridges
Setting Up NAT and Routed Networks
Advanced Networking Concepts
Topics to Learn Libvirt Networking

Chapter 3 : Libvirt Storage

In this section you will learn about Libvirt Storage, as storage concepts are extremely important when building virtualized and cloud environments.

You will know every type of storage that KVM supports – local storage pools, NFS, iSCSI, SAN, Ceph, Gluster, multipathing and redundancy, virtual disk types, and so on.

TopicsRead Time
Understanding Libvirt Storage Options
Setting Up and Managing Storage Pools
Creating and Managing Storage Volumes
Topics to Learn Libvirt Storage

Chapter 4 : Virtual Display Devices and Protocols

In this section you will learn about various virtual machine display types, remote protocols including VNC and Spice, as well as NoVNC, which ensures display portability as we can use a virtual machine console inside a web browser by using NoVNC.

TopicsRead Time
Overview of Virtual Display Technologies
Configuring and Securing Remote Access
Performance Tuning and Troubleshooting
Topics to Learn KVM Virtual Display Devices and Protocols

Chapter 5 : Virtual Machines

In this section you will learn to Virtual Machines Installation, Configuration, and Life Cycle Management, introduces additional ways of deploying and configuring KVM virtual machines, as well as migration processes, which are very important for any kind of production environment.

TopicsRead Time
Creating Your First Virtual Machine
Managing VMs with virsh and Virt-Manager
Snapshots and Cloning VMs
Topics to Learn KVM Virtual Machines

Chapter 6 : Creating and Modifying VM Disks

In this section you will learn to Create and Modify VM Disks, Templates, and Snapshots, various virtual machine image types, virtual machine templating processes, the use of snapshots, and some of the use cases and best practices while using snapshots.

TopicsRead Time
Disk Image Formats and Their Uses
Resizing and Managing Disk Images
Advanced Disk Management
Topics to Learn KVM VM Disks

Chapter 7 : Customize a Virtual Machine with cloud-init

In this section you will learn one of the most fundamental concepts in cloud environments – how to customize a virtual machine image/template post-boot.

Cloud-init is used in almost all of the cloud environments to do post-boot Linux virtual machine configuration, and you will know how it works and how to make it work in your environment.

TopicsRead Time
Introduction to cloud-init
Automating VM Customization with cloud-init
Troubleshooting and Best Practices
Topics to Learn KVM Virtual Machine with cloud-init

Chapter 8 : Automated Windows Guest Deployment and Customization

In this section you will learn Windows Guest Deployment and Customization, with a razor-sharp focus on Microsoft Windows virtual machine templatization and post-boot customization.

For that, you should use cloudbase-init, a concept that’s basically the same as cloud-init, but which is suited for Microsoft-based operating systems only.

TopicsRead Time
Installing Windows on KVM
Automating Windows Deployments
Customizing Windows VMs
Topics to Learn Automated Windows Guest Deployment on KVM

Chapter 9 : Ansible and Scripting for Orchestration and Automation

In this section you will learn to deploy AWX and Ansible, and how to use these concepts in your KVM-based environments.

This is just one of the Ansible usage models that is employed in modern-day IT, as the whole DevOps and infrastructure-as-a-code story gets much more exposure in IT infrastructure all over the world.

TopicsRead Time
Introduction to Ansible for KVM
Writing Ansible Playbooks for VM Management
Scripting for Automation
Topic to Learn Ansible and Scripting with KVM

Chapter 10 : Scaling Out KVM with OpenStack, and AWS

In this section you will learn to the process of building cloud environments based on KVM. OpenStack is the standard approach to delivering just that when using KVM.

In this section, you will learn about all of the OpenStack building blocks and services, how to deploy it from scratch, and describe how to use it in production environments.

You will also learn about public and hybrid cloud concepts by using Amazon Web Services (AWS).

TopicsRead Time
Integrating KVM with OpenStack
Using KVM with AWS
Large-Scale Virtualization Strategies
Topics to Learn KVM with OpenStack, and AWS

Chapter 11 : KVM Virtualization Platform Monitoring and Performance tunning

In this section you will learn a very popular concept of monitoring via the Elasticsearch, Logstash, Kibana (ELK) stack.

It also takes you through the whole process of setting up and integrating the ELK stack with your KVM infrastructure, all the way through to the end result – using dashboards and UIs to monitor your KVM-based environment.

You will also learn about various approaches to tuning and optimization in KVM-based environments by deconstructing all of the infrastructure design principles and putting them to (correct) use. We cover a number of advanced topics here – NUMA, KSM, CPU and memory performance, CPU pinning, the tuning of VirtIO, and block and network devices.

TopicsRead Time
Monitoring KVM Environments
Performance Tuning of KVM Hosts and Guests
Troubleshooting Common Issues
Topics to Learn KVM VM Monitoring and Performance tunning

FAQs (Frequently Asked Questions)

What is KVM (Kernel-based Virtual Machine)?

KVM is an open-source virtualization technology built into Linux that allows you to turn Linux into a hypervisor that hosts multiple, isolated virtual environments or machines.

Who should use KVM?

What are the prerequisites for using KVM?

Is KVM free to use?

How does KVM compare to other virtualization solutions like VMware and Hyper-V?

What operating systems can be run on KVM virtual machines?

How do I install KVM on my system?

What is the difference between QEMU and KVM?

Can KVM be used for production environments?

How does networking work in KVM?

Can I migrate VMs from other hypervisors to KVM?

How do I manage KVM virtual machines?

What is libvirt in KVM?

Are there any best practices for using KVM?

Where can I find more resources to learn about KVM?

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