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BHYVE(8)		  BSD System Manager's Manual		      BHYVE(8)

     bhyve -- run a guest operating system inside a virtual machine

     bhyve [-abehuwxACHPSWY] [-c numcpus] [-g gdbport] [-l lpcdev[,conf]]
	   [-m memsize[K|k|M|m|G|g|T|t]] [-p vcpu:hostcpu]
	   [-s slot,emulation[,conf]] [-U uuid]	vmname

     bhyve is a	hypervisor that	runs guest operating systems inside a virtual

     Parameters	such as	the number of virtual CPUs, amount of guest memory,
     and I/O connectivity can be specified with	command-line parameters.

     If	not using a boot ROM, the guest	operating system must be loaded	with
     bhyveload(8) or a similar boot loader before running bhyve, otherwise, it
     is	enough to run bhyve with a boot	ROM of choice.

     bhyve runs	until the guest	operating system reboots or an unhandled hy-
     pervisor exit is detected.

     -a		 The guest's local APIC	is configured in xAPIC mode.  The
		 xAPIC mode is the default setting so this option is redun-
		 dant.	It will	be deprecated in a future version.

     -A		 Generate ACPI tables.	Required for FreeBSD/amd64 guests.

     -b		 Enable	a low-level console device supported by	FreeBSD	ker-
		 nels compiled with device bvmconsole.	This option will be
		 deprecated in a future	version.

     -c	numcpus	 Number	of guest virtual CPUs.	The default is 1 and the maxi-
		 mum is	16.

     -C		 Include guest memory in core file.

     -e		 Force bhyve to	exit when a guest issues an access to an I/O
		 port that is not emulated.  This is intended for debug	pur-

     -g	gdbport	 For FreeBSD kernels compiled with device bvmdebug, allow a
		 remote	kernel kgdb to be relayed to the guest kernel gdb stub
		 via a local IPv4 address and this port.  This option will be
		 deprecated in a future	version.

     -h		 Print help message and	exit.

     -H		 Yield the virtual CPU thread when a HLT instruction is	de-
		 tected.  If this option is not	specified, virtual CPUs	will
		 use 100% of a host CPU.

     -l	lpcdev[,conf]
		 Allow devices behind the LPC PCI-ISA bridge to	be configured.
		 The only supported devices are	the TTY-class devices com1 and
		 com2 and the boot ROM device bootrom.

     -m	memsize[K|k|M|m|G|g|T|t]
		 Guest physical	memory size in bytes.  This must be the	same
		 size that was given to	bhyveload(8).

		 The size argument may be suffixed with	one of K, M, G or T
		 (either upper or lower	case) to indicate a multiple of	kilo-
		 bytes,	megabytes, gigabytes, or terabytes.  If	no suffix is
		 given,	the value is assumed to	be in megabytes.

		 memsize defaults to 256M.

     -p	vcpu:hostcpu
		 Pin guest's virtual CPU vcpu to hostcpu.

     -P		 Force the guest virtual CPU to	exit when a PAUSE instruction
		 is detected.

     -s	slot,emulation[,conf]
		 Configure a virtual PCI slot and function.

		 bhyve provides	PCI bus	emulation and virtual devices that can
		 be attached to	slots on the bus.  There are 32	available
		 slots,	with the option	of providing up	to 8 functions per

		 slot	     pcislot[:function]	bus:pcislot:function

			     The pcislot value is 0 to 31.  The	optional
			     function value is 0 to 7.	The optional bus value
			     is	0 to 255.  If not specified, the function
			     value defaults to 0.  If not specified, the bus
			     value defaults to 0.


			     hostbridge	| amd_hostbridge

					 Provide a simple host bridge.	This
					 is usually configured at slot 0, and
					 is required by	most guest operating
					 systems.  The amd_hostbridge emula-
					 tion is identical but uses a PCI ven-
					 dor ID	of AMD.

			     passthru	 PCI pass-through device.

			     virtio-net	 Virtio	network	interface.

			     virtio-blk	 Virtio	block storage interface.

			     virtio-rnd	 Virtio	RNG interface.

					 Virtio	console	interface, which ex-
					 poses multiple	ports to the guest in
					 the form of simple char devices for
					 simple	IO between the guest and host

			     ahci	 AHCI controller attached to arbitrary

			     ahci-cd	 AHCI controller attached to an	ATAPI

			     ahci-hd	 AHCI controller attached to a SATA

			     e1000	 Intel e82545 network interface.

			     uart	 PCI 16550 serial device.

			     lpc	 LPC PCI-ISA bridge with COM1 and COM2
					 16550 serial ports and	a boot ROM.
					 The LPC bridge	emulation can only be
					 configured on bus 0.

			     fbuf	 Raw framebuffer device	attached to
					 VNC server.

			     xhci	 eXtensible Host Controller Interface
					 (xHCI)	USB controller.

		 [conf]	     This optional parameter describes the backend for
			     device emulations.	 If conf is not	specified, the
			     device emulation has no backend and can be	con-
			     sidered unconnected.

			     Network devices:



					 If mac	is not specified, the MAC ad-
					 dress is derived from a fixed OUI and
					 the remaining bytes from an MD5 hash
					 of the	slot and function numbers and
					 the device name.

					 The MAC address is an ASCII string in
					 ethers(5) format.

			     Block storage devices:



			     The block-device-options are:

			     nocache   Open the	file with O_DIRECT.

			     direct    Open the	file using O_SYNC.

			     ro	       Force the file to be opened read-only.

				       Specify the logical and physical	sector
				       sizes of	the emulated disk.  The	physi-
				       cal sector size is optional and is
				       equal to	the logical sector size	if not
				       explicitly specified.

			     TTY devices:

			     stdio	 Connect the serial port to the	stan-
					 dard input and	output of the bhyve

			     /dev/xxx	 Use the host TTY device for serial
					 port I/O.

			     Boot ROM device:

			     romfile	 Map romfile in	the guest address
					 space reserved	for boot firmware.

			     Pass-through devices:

					 Connect to a PCI device on the	host
					 at the	selector described by slot,
					 bus, and function numbers.

			     Guest memory must be wired	using the -S option
			     when a pass-through device	is configured.

			     The host device must have been reserved at	boot-
			     time using	the pptdev loader variable as de-
			     scribed in	vmm(4).

			     Virtio console devices:

					 A maximum of 16 ports per device can
					 be created.  Every port is named and
					 corresponds to	a Unix domain socket
					 created by bhyve.  bhyve accepts at
					 most one connection per port at a


					   o   Due to lack of destructors in
					       bhyve, sockets on the filesys-
					       tem must	be cleaned up manually
					       after bhyve exits.

					   o   There is	no way to use the
					       "console	port" feature, nor the
					       console port resize at present.

					   o   Emergency write is advertised,
					       but no-op at present.

			     Framebuffer devices:


					 IP:port   An IP address and a port
						   VNC should listen on.  The
						   default is to listen	on lo-
						   calhost IPv4	address	and
						   default VNC port 5900.
						   Listening on	an IPv6	ad-
						   dress is not	supported.

					 width and height
						   A display resolution, width
						   and height, respectively.
						   If not specified, a default
						   resolution of 1024x768 pix-
						   els will be used.  Minimal
						   supported resolution	is
						   640x480 pixels, and maximum
						   is 1920x1200	pixels.

					 vgaconf   Possible values for this
						   option are "io" (default),
						   "on"	, and "off".  PCI
						   graphics cards have a dual
						   personality in that they
						   are standard	PCI devices
						   with	BAR addressing,	but
						   may also implicitly decode
						   legacy VGA I/O space
						   (0x3c0-3df) and memory
						   space (64KB at 0xA0000).
						   The default "io" option
						   should be used for guests
						   that	attempt	to issue BIOS
						   calls which result in I/O
						   port	queries, and fail to
						   boot	if I/O decode is dis-

						   The "on" option should be
						   used	along with the CSM
						   BIOS	capability in UEFI to
						   boot	traditional BIOS
						   guests that require the
						   legacy VGA I/O and memory
						   regions to be available.

						   The "off" option should be
						   used	for the	UEFI guests
						   that	assume that VGA
						   adapter is present if they
						   detect the I/O ports.  An
						   example of such a guest is
						   OpenBSD in UEFI mode.

						   Please refer	to the bhyve
						   FreeBSD wiki	page
						   for configuration notes of
						   particular guests.

					 wait	   Instruct bhyve to only boot
						   upon	the initiation of a
						   VNC connection, simplifying
						   the installation of operat-
						   ing systems that require
						   immediate keyboard input.
						   This	can be removed for
						   post-installation use.

			     xHCI USB devices:

			     tablet	 A USB tablet device which provides
					 precise cursor	synchronization	when
					 using VNC.

     -S		 Wire guest memory.

     -u		 RTC keeps UTC time.

     -U	uuid	 Set the universally unique identifier (UUID) in the guest's
		 System	Management BIOS	System Information structure.  By de-
		 fault a UUID is generated from	the host's hostname and

     -w		 Ignore	accesses to unimplemented Model	Specific Registers
		 (MSRs).  This is intended for debug purposes.

     -W		 Force virtio PCI device emulations to use MSI interrupts in-
		 stead of MSI-X	interrupts.

     -x		 The guest's local APIC	is configured in x2APIC	mode.

     -Y		 Disable MPtable generation.

     vmname	 Alphanumeric name of the guest.  This should be the same as
		 that created by bhyveload(8).

     bhyve deals with the following signals:

	     Trigger ACPI poweroff for a VM

     Exit status indicates how the VM was terminated:

     0	     rebooted
     1	     powered off
     2	     halted
     3	     triple fault

     If	not using a boot ROM, the guest	operating system must have been	loaded
     with bhyveload(8) or a similar boot loader	before bhyve(4)	can be run.
     Otherwise,	the boot loader	is not needed.

     To	run a virtual machine with 1GB of memory, two virtual CPUs, a virtio
     block device backed by the	/my/image filesystem image, and	a serial port
     for the console:

	   bhyve -c 2 -s 0,hostbridge -s 1,lpc -s 2,virtio-blk,/my/image \
	     -l	com1,stdio -A -H -P -m 1G vm1

     Run a 24GB	single-CPU virtual machine with	three network ports, one of
     which has a MAC address specified:

	   bhyve -s 0,hostbridge -s 1,lpc -s 2:0,virtio-net,tap0 \
	     -s	2:1,virtio-net,tap1 \
	     -s	2:2,virtio-net,tap2,mac=00:be:fa:76:45:00 \
	     -s	3,virtio-blk,/my/image -l com1,stdio \
	     -A	-H -P -m 24G bigvm

     Run an 8GB	quad-CPU virtual machine with 8	AHCI SATA disks, an AHCI ATAPI
     CD-ROM, a single virtio network port, an AMD hostbridge, and the console
     port connected to an nmdm(4) null-modem device.

	   bhyve -c 4 \
	     -s	0,amd_hostbridge -s 1,lpc \
	     -s	1:0,ahci,hd:/images/disk.1,hd:/images/disk.2,\
	   cd:/images/install.iso \
	     -s	3,virtio-net,tap0 \
	     -l	com1,/dev/nmdm0A \
	     -A	-H -P -m 8G

     Run a UEFI	virtual	machine	with a display resolution of 800 by 600	pixels
     that can be accessed via VNC at:

	   bhyve -c 2 -m 4G -w -H \
	     -s	0,hostbridge \
	     -s	3,ahci-cd,/path/to/uefi-OS-install.iso \
	     -s	4,ahci-hd,disk.img \
	     -s	5,virtio-net,tap0 \
	     -s	29,fbuf,tcp=,w=800,h=600,wait \
	     -s	30,xhci,tablet \
	     -s	31,lpc -l com1,stdio \
	     -l	bootrom,/usr/local/share/uefi-firmware/BHYVE_UEFI.fd \

     bhyve(4), nmdm(4),	vmm(4),	ethers(5), bhyvectl(8),	bhyveload(8)

     bhyve first appeared in FreeBSD 10.0.

     Neel Natu <>
     Peter Grehan <>

BSD				  May 3, 2017				   BSD


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