Virt-manager: Difference between revisions

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=== Networking ===
=== Networking ===
The default network starts off as being inactive, you must enable it before it is accessible.
The default network starts off as being inactive, you must enable it before it is accessible.
This can be done by running the following command: <code>virsh net-start default</code>.
This can be done by running the following command:  
 
<code>virsh net-start default</code>
 
Or autostart:
 
<code>virsh net-autostart default</code>


By default this will enable the <code>virbr0</code> virtual network bridge.
By default this will enable the <code>virbr0</code> virtual network bridge.

Revision as of 03:35, 6 February 2024

Requisites

Even though Virt-manager (using the KVM hypervisor) is able to take advantage of virtualisation capabilities without any UEFI/BIOS configuration, best performances demand that host have Vt-x and Vt-d (Intel) or AMD-V and AMD-Vi (AMD) enabled. These settings can usually be found under the UEFI/BIOS settings.

Installation

NixOS

Before 23.11:

virtualisation.libvirtd.enable = true;
programs.dconf.enable = true; # virt-manager requires dconf to remember settings
environment.systemPackages = with pkgs; [ virt-manager ];

After 23.11:

virtualisation.libvirtd.enable = true;
programs.virt-manager.enable = true;

See relevant merge request


You will get a warning when you open it for the first time:

Could not detect a default hypervisor. Make sure the appropriate QEMU/KVM virtualization packages are installed to manage virtualization on this host.

A virtualization connection can be manually added via File->Add Connection

To resolve:

File (in the menu bar) -> Add connection

HyperVisor = QEMU/KVM
Autoconnect = checkmark

Connect

The same can also be achieved declaratively by setting the corresponding dconf settings with home-manager. If you want to do this instead of the imperative configuration described above, add the following snippet to your home-manager configuration:

dconf.settings = {
  "org/virt-manager/virt-manager/connections" = {
    autoconnect = ["qemu:///system"];
    uris = ["qemu:///system"];
  };
};

You may get the following error:

authentication unavailable: no polkit agent available to authenticate action 'org.libvirt.unix.manage'

To resolve, add the user to the libvirtd group:

{
  users.users.<myuser>.extraGroups = [ "libvirtd" ];
}

Networking

The default network starts off as being inactive, you must enable it before it is accessible. This can be done by running the following command:

virsh net-start default

Or autostart:

virsh net-autostart default

By default this will enable the virbr0 virtual network bridge.

Display

The default Video may not allow different resolutions, `Virtio` will allow for more.

Windows Guest

See Virtio-win guest tools for additional drivers for both paravirtual and emulated hardware

Guest Agent

When running NixOS as a guest, enable the QEMU guest agent with:

{
  services.qemuGuest.enable = true;
}

The host must provide the needed virtio serial port under the special name org.qemu.guest_agent.0.