---
title: "How to Install KVM on Ubuntu — Step-by-Step Guide"
source: "https://docs.nexcess.com/hosting/server-administration/linux/how-to-install-kvm-on-ubuntu-step-by-step-guide/"
description: "Install KVM on Ubuntu 22.04. A step-by-step tutorial on KVM installation, network bridging, and using virt-install to create your first virtual machine."
vertical: "Hosting"
date: "2025-10-07"
last_modified: "2026-07-29"
---

# How to Install KVM on Ubuntu — Step-by-Step Guide

## Introduction

Virtualization lets you run multiple operating systems on a single physical server, which saves costs and boosts efficiency. On **Ubuntu**, the **Kernel-based Virtual Machine (KVM)** provides a stable, open-source virtualization platform that turns your server into a flexible environment for hosting virtual machines (VMs).

## Prerequisites

Before you start, make sure your system meets these requirements:

- **Operating system**: Ubuntu 22.04 LTS
- **CPU**: Intel VT-x or AMD-V enabled (hardware virtualization support)
- **RAM**: At least 4 GB (more is recommended for multiple VMs)
- **Disk space**: Minimum 20 GB free for VM images

---

## Instructions

1. **Check for CPU virtualization support.** Run the following command to see if your CPU supports hardware virtualization. If the output is greater than 0, your CPU has the necessary support.

```
egrep -c '(vmx|svm)' /proc/cpuinfo
```

2. **Update your system.** Ensure your system is up-to-date by running the following command:

```
sudo apt update && sudo apt upgrade -y
```

3. **Install KVM, Libvirt, and related utilities.** Use this command to install the necessary packages. qemu-kvm is the main virtualization package, and libvirt-daemon-system manages the VMs. virt-manager provides a graphical interface.

```

sudo apt install qemu-kvm libvirt-daemon-system libvirt-clients bridge-utils virt-manager virt-viewer virt-install
```

4. **Add your user to the libvirt group.** This allows you to manage VMs without sudo. After running this, log out and log back in for the changes to take effect.

```

sudo usermod -aG libvirt $USER
```

5. **Verify the KVM module is loaded.** Run this command to check if the KVM kernel module is active. A successful output will show kvm\_intel or kvm\_amd.

```

lsmod | grep kvm
```

6. **Create a bridge interface for your virtual machines.** This allows your VMs to communicate with the external network. First, open the netplan configuration file. The file name may vary, but it’s typically located in /etc/netplan/.

```

ls /etc/netplan/
```

7. **Edit the netplan file.** Open the identified file with your preferred text editor (e.g., nano).

```
sudo nano /etc/netplan/00-installer-config.yaml
```

8. Replace the file content with a bridge configuration. The example below configures br0 to use DHCP. **Note:** The eno1 should be replaced with your actual physical network interface name (e.g., eth0, enp3s0). You can find this by running the ip a command.

```

YAML
network:
ethernets:

    eno1:

      dhcp4: false

  bridges:

    br0:

      dhcp4: true

      interfaces:

        - eno1

  version: 2
```

9. **Apply the netplan configuration.** Apply the new network configuration. This will restart your networking services and create the br0 bridge.

```
sudo netplan apply
```

10. Create your first virtual machine using the virt-install command.  
      
    The example below creates a VM named ubuntu-server-vm with 2GB of RAM, 2 vCPUs, and a 20GB disk. It uses a local ISO file for installation. **Note:** Update the ISO path and VM name as needed.

```
<br></br>sudo virt-install --name ubuntu-server-vm --ram 2048 --vcpus 2 --cpu host --hvm 
```

- –disk path=/var/lib/libvirt/images/ubuntu-server-vm.qcow2,size=20
- –cdrom /path/to/ubuntu-server.iso –graphics vnc
- –network bridge=br0
- –name: Unique name for the VM.
- –ram: Memory allocation in MB.
- –vcpus: Number of virtual CPUs.
- –disk: Disk image path and size.
- –cdrom: Path to the bootable ISO file.
- –graphics vnc: Enables VNC for graphical access.
- –network bridge=br0: Connects the VM to the bridge network.

 Find your VNC display port by running the following command:

```
sudo virsh domdisplay ubuntu-server-vm
```

**Frequently asked questions**

****My VM can’t connect to the internet.****- Check your netplan configuration and ensure the bridge interface is correctly set up with the right physical interface.
- Ensure your firewall (e.g., ufw) is not blocking traffic. You may need to allow traffic on the br0 interface.

****virt-install command fails with “no bootable device.”****- Confirm the path to your ISO file is correct and the file is not corrupted.
- The user running the command must have read access to the ISO file.

****VNC viewer won’t connect.****Verify that your firewall allows traffic on the VNC port (usually starting from 5900).

---

## Managing your Virtual Machine After Installation

Want to learn more about managing your virtual machine? Check out our article on Managing your virtual machine with Virsh.

## Graphical Management:

Use virt-manager to manage your VMs with a graphical interface.

```

sudo virt-manager
```

## Command-Line Management:

1. List all VMs

```
 sudo virsh list --all
```

2. Start a VM

```
 sudo virsh start your_vm_name
```

3. Shut down a VM

```
 sudo virsh shutdown your_vm_name<br></br>
```