How to create a virtual machine with virt-install

After installing KVM on your Ubuntu or Debian system, the next step is to create a virtual machine using the virt-install command-line tool.

Check existing virtual machines

Before creating a new VM, check if there are any existing ones:

sudo virsh list --all

If no machines exist, the list will be empty.

Create a virtual machine with virt-install

The virt-install command allows you to specify all the VM’s properties. For example:

[!NOTE]
Remember to download the ISO of the operating system you want to install.
It’s recommended to store it in /var/lib/libvirt/images/, which is the default directory for disks and images.

# Example using a local ISO

virt-install --connect qemu:///system     --name ubuntu-24.04-vm     --virt-type kvm --hvm --os-variant=ubuntu24.04     --ram 4096 --vcpus 2 --network network=default     --disk pool=default,size=20,bus=virtio,format=qcow2     --cdrom /var/lib/libvirt/images/ubuntu-24.04.3-live-server-amd64.iso     --boot uefi,cdrom,hd     --noautoconsole

Parameter Explanation

--name vm-test
Name of the virtual machine.
--virt-type kvm
Defines that KVM will be used as the hypervisor.
--hvm
Enables full hardware-assisted virtualization (HVM).
--os-variant=ubuntu25.04
Optimizes the VM configuration according to the OS variant.

[!NOTE]
You can get the full list using the command osinfo-query os.

--ram 2048
Assigns 2048 MB of RAM to the VM.
--vcpus 2
Defines 2 virtual CPUs for the VM.
--network network=default
Connects the VM to the default network (NAT) managed by libvirt.
--graphics vnc,password=remotevnc,listen=0.0.0.0
Configures VNC graphical console access with a password and listens on all interfaces.
--disk pool=default,size=20,bus=virtio,format=qcow2
Creates a 20 GB disk in the default storage pool using the virtio bus and QCOW2 format.
--cdrom /home/$USER/isos/ubuntu-25.04-server.iso
Specifies the ISO file for the operating system installation.
--noautoconsole
Prevents the console from automatically opening after VM creation.
--boot cdrom,hd
Sets the boot order first CD-ROM, then hard disk.

Validate the VM creation

Once created, verify that the VM is running:

virsh list

Example output:

 Id   Name              State
---------------------------------
 1    ubuntu-24.04-vm   running

If your user belongs to the libvirt and kvm groups, you don’t need to use sudo.

Connect to the VM

To connect graphically, you can use virt-viewer. Note that this requires a graphical environment on your host machine.

virt-viewer ubuntu-24.04-vm &

If you set a password for VNC, you will be prompted for it when connecting.

Get the VM’s IP Address

You can retrieve the IP address assigned to the VM with:

virsh domifaddr ubuntu-24.04-vm