Virtual Machines

Shanios ships a full virtualisation stack pre-installed and ready to use. VM disk images live in dedicated Btrfs subvolumes (@libvirt and @qemu) with nodatacow enabled for optimal disk I/O performance. These subvolumes persist across all system updates and rollbacks.

Pre-installed Stack

• libvirt — VM management daemon (libvirtd), accessible via virsh and virt-manager
• QEMU/KVM — hardware-accelerated virtualisation; qemu-base and libvirt are installed as system packages on every edition (shani-core), with libvirtd/virtlogd sockets enabled from first boot. Includes qemu-img for disk image creation/conversion
• systemd-nspawn — lightweight OS containers managed as systemd units (stored in @machines)
• LXC/LXD — full system containers with near-VM isolation (stored in @lxc / @lxd, lxd.socket enabled at boot)
• GNOME Boxes — simple VM manager, pre-installed on the GNOME edition as a Flatpak (org.gnome.Boxes)
• Virt-manager — pre-installed on the KDE Plasma edition as a Flatpak (org.virt_manager.virt-manager + org.virt_manager.virt_manager.Extension.Qemu); install via Flatpak on GNOME or COSMIC editions (COSMIC ships neither manager by default)

Verify the Stack

Everything below should already be true on a fresh install:

# KVM present (if not: enable VT-x/AMD-V in firmware settings)
ls -l /dev/kvm

# Daemon sockets active (socket-activated — they start on first use)
systemctl status libvirtd.socket virtlogd.socket

# Group membership (kvm + libvirt). If just provisioned, log out and back in:
groups | grep -E 'kvm|libvirt'

# Connect and confirm the hypervisor
virsh uri                 # qemu:///system
virsh list --all
virsh net-list --all      # 'default' NAT network should be listed/active

GNOME Boxes

The simplest way to run VMs on Shanios. Pre-installed on the GNOME edition as a Flatpak. For advanced configuration (CPU pinning, GPU passthrough, custom XML), use virt-manager instead.

# Open from the app launcher, or:
flatpak run org.gnome.Boxes

Boxes handles downloading ISOs, creating VMs, and managing snapshots — no manual QEMU or libvirt configuration needed.

Virt-Manager (Full libvirt GUI)

# Pre-installed on KDE Plasma edition. Install on GNOME/COSMIC editions:
flatpak install flathub org.virt_manager.virt-manager
flatpak install flathub org.virt_manager.virt_manager.Extension.Qemu

# Or drive the system daemon directly from the terminal
virsh list --all
virsh start myvm
virsh shutdown myvm
virsh snapshot-create-as myvm snap1

# Create a disk volume inside the dedicated @libvirt pool
virsh vol-create-as default myvm.qcow2 40G --format qcow2

QEMU/KVM — Command Line

# Check KVM is available
ls /dev/kvm
kvm-ok   # or: grep -c vmx /proc/cpuinfo  (Intel) / grep -c svm /proc/cpuinfo  (AMD)

# Quick VM from an ISO (2 CPU cores, 2 GB RAM)
qemu-system-x86_64 \
  -enable-kvm \
  -cpu host \
  -m 2G \
  -smp 2 \
  -cdrom ~/Downloads/ubuntu.iso \
  -drive file=~/vms/ubuntu.qcow2,format=qcow2 \
  -boot d

# Create a disk image
qemu-img create -f qcow2 ~/vms/myvm.qcow2 40G

# Check image info
qemu-img info ~/vms/myvm.qcow2

systemd-nspawn (Lightweight OS Containers)

# Pull an Arch Linux base and boot it as a container
sudo machinectl pull-tar https://dl-cdn.alpinelinux.org/alpine/latest-stable/releases/x86_64/alpine-minirootfs-3.20.0-x86_64.tar.gz alpine

# List machines
machinectl list
machinectl list-images

# Start / stop a machine
sudo machinectl start alpine
sudo machinectl stop alpine

# Login to a running machine
sudo machinectl login alpine

# Enable a machine to start at boot
sudo machinectl enable alpine

LXC / LXD

lxd.socket is enabled at boot. Your user is automatically added to the lxc and lxd groups during installation.

# Initialize LXD (first-time setup)
sudo lxd init --auto

# Launch a container
lxc launch ubuntu:24.04 mycontainer

# List running containers
lxc list

# Execute a command
lxc exec mycontainer -- bash

# Stop / delete
lxc stop mycontainer
lxc delete mycontainer

# Create a snapshot
lxc snapshot mycontainer snap1

# Launch a VM (not a container) with LXD
lxc launch ubuntu:24.04 myvm --vm

Storage Layout

nodatacow is set on @libvirt and @qemu because Copy-on-Write causes fragmentation and performance degradation for large, frequently-written VM disk files.

VM Guest Tools (Running Shanios as a Guest)

If Shanios is running inside a VM (VMware, VirtualBox, QEMU/SPICE), guest tools are pre-installed:

• spice-vdagent — clipboard sharing, dynamic resolution for SPICE/QEMU
• qemu-guest-agent — host–guest coordination for QEMU
• virtualbox-guest-utils — VirtualBox additions
• open-vm-tools — VMware tools

These are grouped under shani-video-guest.target and activate automatically when the relevant package detects the VM environment.

Tips

• Keep VM disk images in /home or the dedicated @libvirt/@qemu subvolumes — not in /var (volatile tmpfs)
• For Windows VMs, use VirtIO drivers for best disk and network performance
• For development environments that need a full OS, prefer Distrobox (lighter, shares your home directory) over a full VM
• LXD VMs offer a middle ground — hardware-level isolation with faster boot than QEMU

Troubleshooting

See Also

• Distrobox — lightweight container-based environments
• Linux Containers (LXC/LXD) — system containers
• systemd-nspawn — lightweight container runtime
• GPU Containers — NVIDIA access in containers
• Bottles — Wine-based Windows app compatibility