BIOS and EFI

Since Quickemu 2.1.0 efi is the default boot option. If you want to override this behaviour then add the following line to you VM configuration to enable legacy BIOS.

•

boot="legacy" - Enable Legacy BIOS boot

Tuning CPU cores, RAM & disks

By default, Quickemu will calculate the number of CPUs cores and RAM to allocate to a VM based on the specifications of your host computer. You can override this default behaviour and tune the VM configuration to your liking.

Add additional lines to your virtual machine configuration:

•

cpu_cores="4" - Specify the number of CPU cores allocated to the VM

•

ram="4G" - Specify the amount of RAM to allocate to the VM

•

disk_size="16G" - Specify the size of the virtual disk allocated to the VM

Disk preallocation

Preallocation mode (allowed values: off (default), metadata, falloc, full). An image with preallocated metadata is initially larger but can improve performance when the image needs to grow.

Specify what disk preallocation should be used, if any, when creating the system disk image by adding a line like this to your VM configuration.

•

preallocation="metadata"

CD-ROM disks

If you want to expose an ISO image from the host to guest add the following line to the VM configuration:

•

fixed_iso="/path/to/image.iso"

Floppy disks

If you're like Alan Pope you'll probably want to mount a floppy disk image in the guest. To do so add the following line to the VM configuration:

•

floppy="/path/to/floppy.img"

File Sharing

All File Sharing options will only expose ~/Public (or localised variations) for the current user to the guest VMs.

Samba 🐧 🍏 🪟

If smbd is available on the host, Quickemu will automatically enable the built-in QEMU support for exposing a Samba share from the host to the guest.

You can install the minimal Samba components on Ubuntu using:

sudo apt install --no-install-recommends samba
    

If everything is set up correctly, the smbd address will be printed when the virtual machine is started. For example:

 - smbd:     On guest: smb://10.0.2.4/qemu
    

If using a Windows guest, right-click on "This PC", click "Add a network location", and paste this address, removing smb: and replacing forward slashes with backslashes (in this example \\10.0.2.4\qemu).

SPICE WebDAV 🐧 🪟

•

TBD

VirtIO-9P 🐧 🍏

•

TBD

Networking

Port forwarding

Add an additional line to your virtual machine configuration. For example:

•

port_forwards=("8123:8123" "8888:80")

In the example above:

•

Port 8123 on the host is forwarded to port 8123 on the guest.

•

Port 8888 on the host is forwarded to port 80 on the guest.

Disable networking

To completely disable all network interfaces in a guest VM add this additional line to your virtual machine configuration:

•

network="none"

Restricted networking

You can isolate the guest from the host (and broader network) using the restrict option, which will restrict networking to just the guest and any virtual devices.

This can be used to prevent software running inside the guest from phoning home while still providing a network inside the guest. Add this additional line to your virtual machine configuration:

•

network="restrict"

Bridged networking

Connect your virtual machine to a preconfigured network bridge. Add an additional line to your virtual machine configuration:

•

network="br0"

If you want to have a persistent MAC address for your bridged network interface in the guest VM you can add macaddr to the virtual machine configuration. QEMU requires that the MAC address is in the range: 52:54:00:AB:00:00 - 52:54:00:AB:FF:FF

So you can generate your own MAC addresses with:

•

macaddr="52:54:00:AB:51:AE"

USB redirection

Quickemu supports USB redirection via SPICE pass-through and host pass-through. Quickemu supports USB redirection via SPICE pass-through and host pass-through.

NOTE! When a USB device is redirected from the host, it will not be usable by host operating system until the guest redirection is stopped. Therefore, do not redirect the input devices, such as the keyboard and mouse, as it will be difficult (or impossible) to revert the situation.

SPICE redirection (recommended)

Using SPICE for USB pass-through is easiest as it doesn't require any elevated permission:

Both spicy from spice-gtk (Input -> Select USB Devices for redirection) and remote-viewer from virt-viewer (File -> USB device selection) support this feature.

•

Start Quickemu with --display spice and then

•

Select Input -> Select USB Device for redirection from the menu to choose which device(s) you want to attach to the guest.

•

**spicy (default)

•

**remote-viewer

To ensure that this functionality works as expected, make sure that you have installed the necessary SPICE Guest Tools on the virtual machine.

Enabling SPICE redirection on NixOS

On NixOS, if you encounter this error:

Error setting facl: Operation not permitted
    

Try setting https://search.nixos.org/options?channel=23.11&show=virtualisation.spiceUSBRedirection.enable&from=0&size=50&sort=relevance&type=packages&query=spiceusbredirec the following option:

virtualisation.spiceUSBRedirection.enable = true;
    

Host redirection (NOT Recommended)

USB host redirection is not recommended, it is provided purely for backwards compatibility to older versions of Quickemu. Using SPICE is preferred, see above.

Add an additional line to your virtual machine configuration. For example:

•

usb_devices=("046d:082d" "046d:085e")

In the example above:

•

The USB device with vendor_id 046d and product_id 082d will be exposed to the guest.

•

The USB device with vendor_id 046d and product_id 085e will be exposed to the guest.

If the USB devices are not writable, quickemu will display the appropriate commands to modify the USB device(s) access permissions, like this:

 - USB:      Host pass-through requested:


              - Sennheiser Communications EPOS GTW 270 on bus 001 device 005 needs permission changes:


                sudo chown -v root:user /dev/bus/usb/001/005


                ERROR! USB permission changes are required 👆
    

TPM

Since Quickemu 2.2.0 a software emulated TPM device can be added to guest virtual machines. Just add tpm="on" to your VM configuration. quickget will automatically add this line to Windows 11 virtual machines.