To install and run Virtual Machine Manager (virt-manager) on Debian 13 (Trixie) without root or sudo privileges, you need to use user-mode QEMU/KVM and configure your user account to manage virtual machines. Here’s how you can do it:

1. Install Required Packages (User-Space)

Since you don’t have root or sudo, you’ll need to:

• Use Flatpak (if available) or
• Install packages in your home directory using --prefix or
• Ask your system administrator to install the required packages.

Option A: Install via Flatpak (Recommended)

If Flatpak is available on your system, you can install virt-manager as a user:

flatpak install flathub org.virt_manager.virt-manager
flatpak run org.virt_manager.virt-manager

Note: Flatpak will handle dependencies (QEMU, libvirt) in a sandboxed environment.

Option B: Manual Installation in User Space

If Flatpak is not an option, you can try installing QEMU and libvirt in your home directory.

Step 1: Install QEMU in User Space

Download and compile QEMU with a custom prefix (e.g., ~/.local):

# Download QEMU source
wget https://download.qemu.org/qemu-8.1.0.tar.xz
tar xvf qemu-8.1.0.tar.xz
cd qemu-8.1.0

# Configure and install in ~/.local
./configure --prefix=$HOME/.local --enable-kvm
make -j$(nproc)
make install

Add ~/.local/bin to your PATH:

export PATH=$HOME/.local/bin:$PATH

Step 2: Install libvirt in User Space

Libvirt is trickier to install without root, but you can try:

# Download libvirt
wget https://libvirt.org/sources/libvirt-10.0.0.tar.xz
tar xvf libvirt-10.0.0.tar.xz
cd libvirt-10.0.0

# Configure and install in ~/.local
./configure --prefix=$HOME/.local --without-qemu --without-openvz --without-vmware --without-xen
make -j$(nproc)
make install

Step 3: Install virt-manager in User Space

# Install Python dependencies
pip install --user virt-manager

# Run virt-manager
python -m virtManager.virtManager

Note: This method may not work perfectly due to missing system-level permissions for KVM.

2. Configure User Permissions for KVM

Even without sudo, you can check if your user is in the kvm group:

groups

If not, ask your system administrator to add you to the kvm group:

sudo usermod -aG kvm $USER

(You’ll need to log out and back in for this to take effect.)

3. Run QEMU/KVM as a Regular User

If you have access to /dev/kvm, you can run QEMU directly:

qemu-system-x86_64 -enable-kvm -m 2G -hda myvm.qcow2

For virt-manager to work, ensure:

• libvirtd is running (if installed system-wide).
• Your user has permissions to /var/run/libvirt/libvirt-sock.

4. Alternative: Use Docker or Podman

If Docker/Podman is available, you can run a container with virt-manager:

podman run -it --rm --privileged --net=host -v /dev:/dev docker.io/virtmanager/virt-manager

5. Troubleshooting

• Error: "Unable to connect to libvirt" → Ensure libvirtd is running and your user has access to the socket.
• Error: "Permission denied on /dev/kvm" → Ask your admin to add you to the kvm group.
• Error: "QEMU not found" → Ensure QEMU is installed and in your PATH.

Summary of Best Approach

Final Recommendation

Use Flatpak if available. If not, ask your system administrator to:

1. Install qemu-kvm, libvirt-daemon-system, and virt-manager system-wide.
2. Add your user to the kvm and libvirt groups.