Installing KVM on RHEL : Complete Guide

So You want to have a highly stable & open-source virtualization platform! It’s Here, KVM (Kernel-Based Virtual Machine ) is the best, Yes the best module ever there that provides outstanding virtualization performance, once you have installed KVM on RHEL whether your server or desktop, you’ll discover how powerful it is, so let’s get started.

What is KVM?

Simply put, KVM stands for Kernel-Based Virtual Machine, It’s the best open-source virtualization technology for the GNU/Linux OS. Originally developed in the middle of 2006 and merged into the Linux Kernel since the release number 2.6.20 which became available in 2007.

Features of KVM.

Well, KVM is a Module in the Linux Kernel, and being a module that resides in the Linux Kernel means that it converts the Linux Kernel into a Type-1 Hypervisor so it gives you a native performance since it runs directly on the host machines, Also this minimizing the overhead and providing a near metal performance.

Prerequisites before running KVM on RHEL?

1- To get the best out of this tutorial you need to have a server or a laptop running Red Hat Enterprise Linux ( RHEL ) Operating System with a valid subscription.

If you don’t have a RHEL Subscription, follow our tutorial, which is linked below, on how to obtain a free RHEL Subscription.

How To Obtain a RHEL Subscription For Free: Complete Guide

2- At least 15 GB or more of free disk space to run at least one virtual machine.

3- 6 GB or RAM or more to run virtual machines.

Steps to install KVM on RHEL?

1- Check If Virtualization Technology is supported & enabled in the BIOS, By Default most of the hardware vendors support this feature. To Verify that the Virtualization Technology is enabled execute the following command :

For Intel-Based Processors

sudo lscpu | grep -i vmx

If Your Machine’s Processor is AMD, type the following and notice the word ‘svm’ in the result

sudo lscpu | grep -i svm

Or You can only run the following command and make sure that the VT-x does exist in the Virtualization features section of the output

sudo lscpu

2- Make sure that the KVM Module is loaded, type the following command

sudo lsmod | grep -i kvm

The result should be something like this

kvm_intel 446464 4
kvm 1400832 3 kvm_intel

3- Update Your Operating System

sudo dnf update

4- Now install all the required virtualization software by typing the following commands

sudo dnf groupinstall "Virtualization Host"

sudo dnf install virt-install virt-manager virt-viewer tigervnc cockpit cockpit-machines

5- Add Your user to the KVM, QEMU & libvirt groups

usermod -aG kvm $USER

usermod -aG qemu $USER

usermod -aG libvirt $USER

6- If You are using RHEL 8 make sure that the following service is enabled

sudo systemctl is-enabled libvirtd.service

And If You are using RHEL 9 make sure that the following modular libvirt daemons are enabled

You can read more about the changes in libvirt in RHEL 9 from Here.

sudo su -

for drivers in qemu network nodedev nwfilter secret storage interface; do systemctl enable virt${drivers}d{,-ro,-admin}.socket; done

for drivers in qemu network nodedev nwfilter secret storage interface; do systemctl is-enabled virt${drivers}d{,-ro,-admin}.socket; done

6- Reboot Your Server or Your RHEL Desktop

reboot

7- Now After Reboot run the following command to make sure that the modular libvirt daemons have been started automatically

sudo su -

virt-host-validate

for drivers in qemu network nodedev nwfilter secret storage interface; do systemctl is-active virt${drivers}d{,-ro,-admin}.socket; done

for drivers in qemu network nodedev nwfilter secret storage interface; do systemctl status virt${drivers}d{,-ro,-admin}.socket; done

8- Create a Directory that will hold the ISO files of the Virtual Machines that will be installed, You may name the directory as ISODomain. Type the following commands to create that directory

sudo mkdir -p /KVM/ISODomain

sudo virsh pool-define-as --type dir --name ISODomain --source-path /KVM/ISODomain/ --target /KVM/ISODomain/

sudo virsh pool-autostart --pool ISODomain

sudo virsh pool-start --pool ISODomain

sudo virsh pool-list --all –details

9- Create a Directory that will hold the Virtual Machines Disks, You may name it like VMsDomains

sudo mkdir -p /KVM/VMsDomains

sudo virsh pool-define-as --type dir --name VMsDomains --source-path /KVM/VMsDomains/ --target /KVM/VMsDomains/

sudo virsh pool-autostart --pool VmsDomains

sudo virsh pool-start --pool VmsDomains

sudo virsh pool-list --all –details

10- Download The ISO Files and move them to the ISODomain Directory, For Example, If You’ve downloaded rhel-9.5-x86_64-dvd.iso, ubuntu-22.04.5-desktop-amd64.iso & windows 10, You’ve to move all of them to that directory. The following command is an example of moving the rhel iso file

sudo mv /home/$USER/Downloads/ rhel-9.5-x86_64-dvd.iso /KVM/ISODomain/

Then

restorecon -Rv /KVM/

11- Now You can build a Virtual Machine by either using the virt-install like

virt-install \

–arch x86_64 \

-name MyVM \

–hvm \

–vcpus sockets=1,cores=2,threads=1 \

–memory 2084 \

–disk pool=VMsDomain,size=10,formart=qcow2,target.bus=virtio,device=disk \

–boot hd,cdrom \

–cdrom /KVM/ISODomain/rhel-9.5-x86_64-dvd.iso \

–network network=default,model.type=virtio \

–graphics type=vnc

Or By using the virt-manager graphical application, to launch it type the following

sudo virt-manager

and follow the steps starting from selecting the ISO file then the disk size for the Virtual Machine till finally the name of the Virtual Machine

Conclusion

In this guide, we have explored what KVM is and how we can use it to build our free and open-source virtualization environment. If You face any issues while setting it up please let us know as we will happily have your feedback.