Pen-Test Lab PART 3 - Installing an Ubuntu VM on QEMU/KVM

This guide will walk you through installing an Ubuntu virtual machine using QEMU/KVM.

Prerequisites

• Ubuntu ISO file (already downloaded and moved to /home/<USER>/ISO/Linux/ubuntu-24.04.2-desktop-amd64.iso)
• QEMU/KVM environment set up (from the main tutorial)

Step 1: Create the Ubuntu VM

sudo virt-install \
  --name ubuntu-vm \
  --memory 4096 \
  --vcpus 2 \
  --cpu host \
  --disk size=30 \
  --cdrom /home/<USER>/ISO/Linux/ubuntu-24.04.2-desktop-amd64.iso \
  --os-variant ubuntu24.04 \
  --graphics spice \
  --video virtio \
  --channel spicevmc

If you're not sure about the correct --os-variant parameter, check available options:

sudo apt install libosinfo-bin
osinfo-query os | grep -i ubuntu

If ubuntu24.04 isn't available, you can use ubuntu22.04 or simply ubuntu:

sudo virt-install \
  --name ubuntu-vm \
  --memory 4096 \
  --vcpus 2 \
  --cpu host \
  --disk size=30 \
  --cdrom /home/<USER/ISO/Linux/ubuntu-24.04.2-desktop-amd64.iso \
  --os-variant ubuntu \
  --graphics spice \
  --video virtio \
  --channel spicevmc

Step 2: Connect to the VM

Connect to your VM using virt-viewer:

virt-viewer --connect qemu:///system ubuntu-vm

Or via Cockpit at https://localhost:9090

Step 3: Install Ubuntu

1. Once connected, follow the standard Ubuntu installation process:
2. Select your language
3. Choose "Install Ubuntu"
4. Select keyboard layout
5. Choose "Normal installation"
6. Select "Erase disk and install Ubuntu" (this erases only the virtual disk)
7. Select your timezone
8. Create your user account and password

9. Wait for installation to complete and restart when prompted

10. After installation, the VM will restart. You may need to remove the installation media:

11. If the VM tries to boot from the ISO again, shut it down
12. Edit the VM configuration to disconnect the ISO:

sudo virsh change-media ubuntu-vm sda --eject

• Or use Cockpit to detach the ISO in the "Disks" section
• Start the VM again

Step 4: Install VM Guest Additions (Optional but Recommended)

For better integration with the host system:

# Inside the Ubuntu VM, open a terminal and run:
sudo apt update
sudo apt install -y spice-vdagent

For better performance and additional features:

sudo apt install -y qemu-guest-agent

Then on the host, enable the QEMU guest agent:

sudo virsh shutdown ubuntu-vm
sudo virsh dumpxml ubuntu-vm > /tmp/ubuntu-vm.xml

Edit the XML file to add the guest agent channel:

sudo nano /tmp/ubuntu-vm.xml

Add this section if it doesn't exist:

<channel type='unix'>
  <target type='virtio' name='org.qemu.guest_agent.0'/>
</channel>

Update the VM definition:

sudo virsh define /tmp/ubuntu-vm.xml
sudo virsh start ubuntu-vm

Step 5: Optimize Performance (Optional)

For better disk performance, convert to virtio disk:

sudo virsh shutdown ubuntu-vm
sudo virsh edit ubuntu-vm

Change the disk bus from sata to virtio:

<disk type='file' device='disk'>
  ...
  <target dev='vda' bus='virtio'/>
  ...
</disk>

Shared Folders with Ubuntu VM

If you want to share files between the host and Ubuntu VM:

1. The simplest approach is to use SAMBA (as described in the Windows VM guide)

2. Alternatively, you can use SSH file transfer:

# Inside the Ubuntu VM, install SSH server
sudo apt install -y openssh-server

# On the host, use scp to copy files
scp /path/to/file username@ubuntu-vm-ip:/destination/path/

# Or use SFTP in your file manager:
# Enter sftp://username@ubuntu-vm-ip/ in your file manager address bar

1. For drag and drop functionality, ensure spice-vdagent is installed

Remember to use the VM service script to start all necessary services before launching your Ubuntu VM:

vm-start