+cpu\_cores
+ Valid for the KVM hypervisor.
+
+ Number of emulated CPU cores.
+
+cpu\_threads
+ Valid for the KVM hypervisor.
+
+ Number of emulated CPU threads.
+
+cpu\_sockets
+ Valid for the KVM hypervisor.
+
+ Number of emulated CPU sockets.
+
+soundhw
+ Valid for the KVM and XEN hypervisors.
+
+ Comma separated list of emulated sounds cards, or "all" to enable
+ all the available ones.
+
+cpuid
+ Valid for the XEN hypervisor.
+
+ Modify the values returned by CPUID_ instructions run within instances.
+
+ This allows you to enable migration between nodes with different CPU
+ attributes like cores, threads, hyperthreading or SS4 support by hiding
+ the extra features where needed.
+
+ See the XEN documentation for syntax and more information.
+
+.. _CPUID: http://en.wikipedia.org/wiki/CPUID
+
+usb\_devices
+ Valid for the KVM hypervisor.
+
+ Space separated list of usb devices. These can be emulated devices
+ or passthrough ones, and each one gets passed to kvm with its own
+ ``-usbdevice`` option. See the **qemu**\(1) manpage for the syntax
+ of the possible components. Note that values set with this
+ parameter are split on a space character and currently don't support
+ quoting. For backwards compatibility reasons, the RAPI interface keeps
+ accepting comma separated lists too.
+
+vga
+ Valid for the KVM hypervisor.
+
+ Emulated vga mode, passed the the kvm -vga option.
+
+kvm\_extra
+ Valid for the KVM hypervisor.
+
+ Any other option to the KVM hypervisor, useful tweaking anything
+ that Ganeti doesn't support. Note that values set with this
+ parameter are split on a space character and currently don't support
+ quoting.
+
+machine\_version
+ Valid for the KVM hypervisor.
+
+ Use in case an instance must be booted with an exact type of
+ machine version (due to e.g. outdated drivers). In case it's not set
+ the default version supported by your version of kvm is used.
+
+kvm\_path
+ Valid for the KVM hypervisor.
+
+ Path to the userspace KVM (or qemu) program.
+
+vnet\_hdr
+ Valid for the KVM hypervisor.
+
+ This boolean option determines whether the tap devices used by the
+ KVM paravirtual nics (virtio-net) will get created with VNET_HDR
+ (IFF_VNET_HDR) support.
+
+ If set to false, it effectively disables offloading on the virio-net
+ interfaces, which prevents host kernel tainting and log flooding,
+ when dealing with broken or malicious virtio-net drivers.
+
+ It is set to ``true`` by default.