5 Easy Steps to Set Up VMs on Ubuntu Server

Virtualization has become an essential aspect of modern computing, allowing users to run multiple operating systems on a single physical machine. Ubuntu Server, a popular choice among Linux administrators, provides an excellent platform for setting up virtual machines (VMs). In this article, we will guide you through 5 easy steps to set up VMs on Ubuntu Server, leveraging the power of KVM (Kernel-based Virtual Machine) hypervisor.

Ubuntu Server's versatility and the KVM hypervisor's efficiency make them an ideal combination for virtualization needs. The KVM hypervisor is a part of the Linux kernel and allows for efficient and secure virtualization. With KVM, you can create and manage virtual machines with ease, making it a popular choice among Linux administrators.

Prerequisites for Setting Up VMs on Ubuntu Server

Before diving into the setup process, ensure your Ubuntu Server meets the necessary prerequisites. Firstly, you need a 64-bit processor with hardware virtualization support (Intel VT or AMD-V). You can check for virtualization support using tools like `lscpu` or `egrep -c '(vmx|svm)' /proc/cpuinfo`. Additionally, your server should have sufficient RAM and storage to accommodate the host operating system, the virtual machines, and any additional software you plan to install.

It is also crucial to update your Ubuntu Server to the latest version to ensure you have the most recent security patches and software updates. You can update your system using the `apt update` and `apt upgrade` commands.

Step 1: Install KVM on Ubuntu Server

The first step is to install the KVM hypervisor on your Ubuntu Server. This can be achieved by running the following commands:

sudo apt update
sudo apt install -y qemu-kvm libvirt-daemon-system libvirt-clients bridge-utils

These commands update your package list and install the necessary packages for KVM, including `qemu-kvm` for the hypervisor, `libvirt-daemon-system` and `libvirt-clients` for management tools, and `bridge-utils` for network configuration.

Verify KVM Installation

After installation, verify that KVM is properly installed and your system supports hardware virtualization:

lsmod | grep kvm

If KVM is loaded, you should see `kvm` and possibly `kvm_intel` or `kvm_amd` in the output, indicating that the KVM module is active.

Step 2: Prepare the Network for VMs

Configuring the network is crucial for your VMs to communicate with the host and the external network. Ubuntu Server uses `bridge-utils` to create a network bridge that allows VMs to share the host's network interface.

Create a network bridge by editing the `netplan` configuration file. Typically, you'll find the configuration file under `/etc/netplan/`:

sudo nano /etc/netplan/01-netcfg.yaml

Add the following configuration to create a bridge named `br0`:

network:
  version: 2
  renderer: networkd
  wifis:
    eth0:
      dhcp4: no
      dhcp6: no
      addresses: [192.168.1.100/24]
      gateway4: 192.168.1.1
      nameservers:
        addresses: [8.8.8.8, 8.8.4.4]
  bridges:
    br0:
      dhcp4: yes
      interfaces:
        - eth0

Apply the changes:

sudo netplan apply

Step 3: Create a Virtual Machine

With KVM installed and the network configured, you're ready to create your first VM. Use the `virt-install` command to create a VM:

sudo virt-install --name ubuntu-vm --ram 4096 --disk path=/var/lib/libvirt/images/ubuntu-vm.img,size=20 --network bridge=br0 --os-variant ubuntu20.04 --vcpus 2 --graphics none --console pty --cdrom /path/to/ubuntu-20.04.6-desktop-amd64.iso

Customize the command with your specifications, such as VM name, RAM, disk size, network bridge, OS variant, number of CPUs, and the path to your ISO file.

Step 4: Manage Your Virtual Machines

After creating your VMs, you can manage them using the `virsh` command-line tool. Here are a few basic management commands:

• List all VMs: `virsh list`
• Start a VM: `virsh start ubuntu-vm`
• Stop a VM: `virsh shutdown ubuntu-vm`
• Remove a VM: `virsh undefine ubuntu-vm`

Step 5: Accessing Your Virtual Machines

To access your VMs, you can use the `virt-viewer` tool:

sudo virt-viewer -c qemu:///system --wait --vm ubuntu-vm

This command connects you to the VM's console, allowing you to interact with it as if you were sitting in front of it.