[thumbnail="screenshot/gui-create-vm-os.png"]
-When creating a VM, setting the proper Operating System(OS) allows {pve} to
-optimize some low level parameters. For instance Windows OS expect the BIOS
-clock to use the local time, while Unix based OS expect the BIOS clock to have
-the UTC time.
+When creating a virtual machine (VM), setting the proper Operating System(OS)
+allows {pve} to optimize some low level parameters. For instance Windows OS
+expect the BIOS clock to use the local time, while Unix based OS expect the
+BIOS clock to have the UTC time.
+[[qm_system_settings]]
+System Settings
+~~~~~~~~~~~~~~~
+
+On VM creation you can change some basic system components of the new VM. You
+can specify which xref:qm_display[display type] you want to use.
+[thumbnail="screenshot/gui-create-vm-system.png"]
+Additionally, the xref:qm_hard_disk[SCSI controller] can be changed.
+If you plan to install the QEMU Guest Agent, or if your selected ISO image
+already ships and installs it automatically, you may want to tick the 'Qemu
+Agent' box, which lets {pve} know that it can use its features to show some
+more information, and complete some actions (for example, shutdown or
+snapshots) more intelligently.
+
+{pve} allows to boot VMs with different firmware and machine types, namely
+xref:qm_bios_and_uefi[SeaBIOS and OVMF]. In most cases you want to switch from
+the default SeabBIOS to OVMF only if you plan to use
+xref:qm_pci_passthrough[PCIe pass through]. A VMs 'Machine Type' defines the
+hardware layout of the VM's virtual motherboard. You can choose between the
+default https://en.wikipedia.org/wiki/Intel_440FX[Intel 440FX] or the
+https://ark.intel.com/content/www/us/en/ark/products/31918/intel-82q35-graphics-and-memory-controller.html[Q35]
+chipset, which also provides a virtual PCIe bus, and thus may be desired if
+one want's to pass through PCIe hardware.
[[qm_hard_disk]]
Hard Disk
https://en.wikipedia.org/wiki/Trim_%28computing%29], when the VM's filesystem
marks blocks as unused after deleting files, the controller will relay this
information to the storage, which will then shrink the disk image accordingly.
-For the guest to be able to issue _TRIM_ commands, you must either use a
-*VirtIO SCSI* (or *VirtIO SCSI Single*) controller or set the *SSD emulation*
-option on the drive. Note that *Discard* is not supported on *VirtIO Block*
-drives.
+For the guest to be able to issue _TRIM_ commands, you must enable the *Discard*
+option on the drive. Some guest operating systems may also require the
+*SSD Emulation* flag to be set. Note that *Discard* on *VirtIO Block* drives is
+only supported on guests using Linux Kernel 5.0 or higher.
If you would like a drive to be presented to the guest as a solid-state drive
rather than a rotational hard disk, you can set the *SSD emulation* option on
.Fixed Memory Allocation
[thumbnail="screenshot/gui-create-vm-memory.png"]
-When setting memory and minimum memory to the same amount
+ghen setting memory and minimum memory to the same amount
{pve} will simply allocate what you specify to your VM.
Even when using a fixed memory size, the ballooning device gets added to the
~~~~~~~~~~~~~
In order to properly emulate a computer, QEMU needs to use a firmware.
-By default QEMU uses *SeaBIOS* for this, which is an open-source, x86 BIOS
-implementation. SeaBIOS is a good choice for most standard setups.
+Which, on common PCs often known as BIOS or (U)EFI, is executed as one of the
+first steps when booting a VM. It is responsible for doing basic hardware
+initialization and for providing an interface to the firmware and hardware for
+the operating system. By default QEMU uses *SeaBIOS* for this, which is an
+open-source, x86 BIOS implementation. SeaBIOS is a good choice for most
+standard setups.
There are, however, some scenarios in which a BIOS is not a good firmware
to boot from, e.g. if you want to do VGA passthrough. footnote:[Alex Williamson has a very good blog entry about this.
with a press of the ESC button during boot), or you have to choose
SPICE as the display type.
+[[qm_ivshmem]]
+Inter-VM shared memory
+~~~~~~~~~~~~~~~~~~~~~~
+
+You can add an Inter-VM shared memory device (`ivshmem`), which allows one to
+share memory between the host and a guest, or also between multiple guests.
+
+To add such a device, you can use `qm`:
+
+ qm set <vmid> -ivshmem size=32,name=foo
+
+Where the size is in MiB. The file will be located under
+`/dev/shm/pve-shm-$name` (the default name is the vmid).
+
+NOTE: Currently the device will get deleted as soon as any VM using it got
+shutdown or stopped. Open connections will still persist, but new connections
+to the exact same device cannot be made anymore.
+
+A use case for such a device is the Looking Glass
+footnote:[Looking Glass: https://looking-glass.hostfission.com/] project,
+which enables high performance, low-latency display mirroring between
+host and guest.
+
+[[qm_audio_device]]
+Audio Device
+~~~~~~~~~~~~
+
+To add an audio device run the following command:
+
+----
+qm set <vmid> -audio0 device=<device>
+----
+
+Supported audio devices are:
+
+* `ich9-intel-hda`: Intel HD Audio Controller, emulates ICH9
+* `intel-hda`: Intel HD Audio Controller, emulates ICH6
+* `AC97`: Audio Codec '97, useful for older operating systems like Windows XP
+
+NOTE: The audio device works only in combination with SPICE. Remote protocols
+like Microsoft's RDP have options to play sound. To use the physical audio
+device of the host use device passthrough (see
+xref:qm_pci_passthrough[PCI Passthrough] and
+xref:qm_usb_passthrough[USB Passthrough]).
+
[[qm_startup_and_shutdown]]
Automatic Start and Shutdown of Virtual Machines
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
endif::wiki[]
Hookscripts
-~~~~~~~~~~~
+-----------
You can add a hook script to VMs with the config property `hookscript`.