man/man8/bhyve.8

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.\" Portions Copyright 2022 OmniOS Community Edition (OmniOSce) Association.
.\"
.Dd February 26, 2022
.Dt BHYVE 8
.Os
.Sh NAME
.Nm bhyve
.Nd "run a guest operating system inside a virtual machine"
.Sh SYNOPSIS
.Nm
.Op Fl aCDdeHhPSuWwxY
.Oo
.Sm off
.Fl c\~
.Oo
.Op Cm cpus=
.Ar numcpus
.Oc
.Op Cm ,sockets= Ar n
.Op Cm ,cores= Ar n
.Op Cm ,threads= Ar n
.Oc
.Sm on
.Oo
.Sm off
.Fl G\~
.Oo Ar w Oc
.Oo Ar bind_address Cm \&: Oc
.Ar port
.Oc
.Sm on
.Oo Fl B
.Sm off
.Ar type Ns \&,
.Op Ar key Ns = Ns Ar value
.Oo \&, Ns Ar key Ns = Ns Ar value Ns Oc \&...
.Oc
.Sm on
.Op Fl k Ar config_file
.Op Fl K Ar layout
.Oo Fl l
.Sm off
.Ar lpcdev Op Cm \&, Ar conf
.Sm on
.Oc
.Sm off
.Oo Fl m\~
.Ar memsize
.Oo
.Cm K | k | M | m | G | g | T | t
.Oc
.Sm on
.Oc
.Op Fl o Ar var Ns Cm = Ns Ar value
.Op Fl r Ar file
.Sm off
.Oo Fl s\~
.Ar slot Cm \&, Ar emulation Op Cm \&, Ar conf
.Sm on
.Oc
.Op Fl U Ar uuid
.Ar vmname
.Nm
.Fl l Cm help
.Nm
.Fl s Cm help
.Sh DESCRIPTION
.Nm
is a hypervisor that runs guest operating systems inside a
virtual machine.
.Pp
Parameters such as the number of virtual CPUs, amount of guest memory, and
I/O connectivity can be specified with command-line parameters.
.Pp
.Nm
runs until the guest operating system reboots or an unhandled hypervisor
exit is detected.
.Sh OPTIONS
.Bl -tag -width 10n
.It Fl a
The guest's local APIC is configured in xAPIC mode.
The xAPIC mode is the default setting so this option is redundant.
It will be deprecated in a future version.
.It Xo
.Fl B
.Sm off
.Ar type Ns \&,
.Op Ar key Ns = Ns Ar value
.Oo \&, Ns Ar key Ns = Ns Ar value Ns Oc \&...
.Sm on
.Xc
Configure smbios data.
.Ar type
must be set to
.Sy 1 .
Supported keys are:
.Sy manufacturer ,
.Sy product ,
.Sy version ,
.Sy serial ,
.Sy sku ,
.Sy family
and
.Sy uuid .
.It Xo Fl c
.Sm off
.Op Oo Cm cpus= Oc Ar numcpus
.Op Cm ,sockets= Ar n
.Op Cm ,cores= Ar n
.Op Cm ,threads= Ar n
.Xc
.Sm on
Number of guest virtual CPUs
and/or the CPU topology.
The default value for each of
.Ar numcpus ,
.Ar sockets ,
.Ar cores ,
and
.Ar threads
is 1.
The current maximum number of guest virtual CPUs is 32.
If
.Ar numcpus
is not specified then it will be calculated from the other arguments.
The topology must be consistent in that the
.Ar numcpus
must equal the product of
.Ar sockets ,
.Ar cores ,
and
.Ar threads .
If a
.Ar setting
is specified more than once the last one has precedence.
.It Fl C
Include guest memory in core file.
.It Fl D
Destroy the VM on guest initiated power-off.
.It Fl d
Suspend CPUs at boot.
.It Fl e
Force
.Nm
to exit when a guest issues an access to an I/O port that is not emulated.
This is intended for debug purposes.
.It Fl G Xo
.Sm off
.Oo Ar w Oc
.Oo Ar bind_address Cm \&: Oc
.Ar port
.Sm on
.Xc
Start a debug server that uses the GDB protocol to export guest state to a
debugger.
An IPv4 TCP socket will be bound to the supplied
.Ar bind_address
and
.Ar port
to listen for debugger connections.
Only a single debugger may be attached to the debug server at a time.
If the option begins with
.Sq w ,
.Nm
will pause execution at the first instruction waiting for a debugger to attach.
.It Fl H
Yield the virtual CPU thread when a HLT instruction is detected.
If this option is not specified, virtual CPUs will use 100% of a host CPU.
.It Fl h
Print help message and exit.
.It Fl k Ar config_file
Set configuration variables from a simple, key-value config file.
Each line of the config file is expected to consist of a config variable
name, an equals sign
.Pq Sq = ,
and a value.
No spaces are permitted between the variable name, equals sign, or
value.
Blank lines and lines starting with
.Sq #
are ignored.
See
.Xr bhyve_config 5
for more details.
.It Fl K Ar layout
Specify the keyboard layout.
The value that can be specified sets the file name in
.Pa /usr/share/bhyve/kbdlayout .
This specification only works when loaded with UEFI mode for VNC.
When using a VNC client that supports QEMU Extended Key Event Message
.Pq e.g. TigerVNC ,
this option isn't needed.
When using a VNC client that doesn't support QEMU Extended Key Event Message
.Pq e.g. tightVNC ,
the layout defaults to the US keyboard unless specified otherwise.
.It Fl l Cm help
Print a list of supported LPC devices.
.It Fl l Ar lpcdev Ns Op \&, Ns Ar conf
Allow devices behind the LPC PCI-ISA bridge to be configured.
The only supported devices are the TTY-class devices
.Cm com1 , com2 , com3
and
.Cm com4 ,
the boot ROM device
.Cm bootrom ,
and the debug/test device
.Cm pc-testdev .
.Pp
The possible values for the
.Ar conf
argument are listed in the
.Fl s
flag description.
.It Xo
.Fl m Ar memsize Ns Oo
.Sm off
.Cm K | k | M | m | G | g | T | t
.Sm on
.Oc
.Xc
Set the guest physical memory size.
The size argument may be suffixed with one of
.Cm K , M , G
or
.Cm T
.Pq either upper or lower case
to indicate a multiple of kibibytes, mebibytes, gibibytes, or tebibytes.
If no suffix is given, the value is assumed to be in mebibytes.
.Pp
The default is 256MiB.
.It Fl o Ar var Ns Cm = Ns Ar value
Set the configuration variable
.Ar var
to
.Ar value .
.It Fl P
Force the guest virtual CPU to exit when a PAUSE instruction is detected.
.It Fl S
Wire guest memory.
.It Fl s Cm help
Print a list of supported PCI devices.
.It Fl s Ar slot Ns Cm \&, Ns Ar emulation Ns Op Cm \&, Ns Ar conf
Configure a virtual PCI slot and function.
.Pp
.Nm
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.
.Pp
The
.Ar slot
can be specified in one of the following formats:
.Pp
.Bl -bullet -compact
.It
.Ar pcislot
.It
.Sm off
.Ar pcislot Cm \&: Ar function
.Sm on
.It
.Sm off
.Ar bus Cm \&: Ar pcislot Cm \&: Ar function
.Sm on
.El
.Pp
The
.Ar pcislot
value is 0 to 31.
The optional
.Ar function
value is 0 to 7.
The optional
.Ar bus
value is 0 to 255.
If not specified, the
.Ar function
value defaults to 0.
If not specified, the
.Ar bus
value defaults to 0.
.Pp
The
.Ar emulation
argument can be one of the following:
.Bl -tag -width "amd_hostbridge"
.It Cm hostbridge
A simple host bridge.
This is usually configured at slot 0, and is required by most guest
operating systems.
.It Cm amd_hostbridge
Emulation identical to
.Cm hostbridge
but using a PCI vendor ID of AMD.
.It Cm passthru
PCI pass-through device.
.It Cm virtio-net-viona
Accelerated Virtio network interface.
.It Cm virtio-net
Legacy Virtio network interface.
.It Cm virtio-blk
Virtio block storage interface.
.It Cm virtio-9p
Virtio 9p (VirtFS) interface.
.It Cm virtio-rnd
Virtio random number generator interface.
.It Cm virtio-console
Virtio console interface, which exposes multiple ports
to the guest in the form of simple char devices for simple IO
between the guest and host userspaces.
.It Cm ahci
AHCI controller attached to arbitrary devices.
.It Cm ahci-cd
AHCI controller attached to an ATAPI CD/DVD.
.It Cm ahci-hd
AHCI controller attached to a SATA hard drive.
.It Cm e1000
Intel e82545 network interface.
.It Cm uart
PCI 16550 serial device.
.It Cm lpc
LPC PCI-ISA bridge with COM1, COM2, COM3, and COM4 16550 serial ports,
a boot ROM, and, optionally, the debug/test device.
The LPC bridge emulation can only be configured on bus 0.
.It Cm fbuf
Raw framebuffer device attached to VNC server.
.It Cm xhci
eXtensible Host Controller Interface (xHCI) USB controller.
.It Cm nvme
NVM Express (NVMe) controller.
.El
.Pp
The optional parameter
.Ar conf
describes the backend for device emulations.
If
.Ar conf
is not specified, the device emulation has no backend and can be
considered unconnected.
.Pp
.Sy Host Bridge Devices
.Bl -tag -width 10n
.It Cm model Ns = Ns Ar model
Specify a hostbridge model to emulate.
Valid model strings, and their associated vendor and device IDs are:
.Sy amd Pq 0x1022/0x7432 ,
.Sy netapp Pq 0x1275/0x1275 ,
.Sy i440fx Pq 0x8086/0x1237
and
.Sy q35 Pq 0x8086/0x29b0 .
The default value of
.Ar model
is
.Cm netapp .
.It Cm vendor Ns = Ns Ar vendor
PCI vendor ID.
.It Cm devid Ns = Ns Ar devid
PCI device ID.
.El
.Pp
Providing extra configuration parameters for a host bridge is optional, but if
parameters are provided then either
.Va model
by itself, or both of
.Va vendor
and
.Va devid
must be specified.
.Pp
.Sy Accelerated Virtio Network Backends :
.Bl -tag -width 10n
.It Oo Cm vnic Ns = Oc Ns Ar vnic Ns Oo , Ns Cm feature_mask Ns = Ns Ar mask Oc
.Pp
.Ar vnic
is the name of a configured virtual NIC on the system.
.Ar mask
is applied to the virtio feature flags which are advertised to the guest.
Bits set in the
.Ar mask
value are removed from the advertised features.
.El
.Pp
.Sy Other Network Backends :
.Bl -tag -width 10n
.It Oo Cm vnic Ns = Oc Ns Ar vnic Ns Oo , Ns Ar network-backend-options Oc
.Pp
.Ar vnic
is the name of a configured virtual NIC on the system.
.El
.Pp
The
.Ar network-backend-options
are:
.Bl -tag -width 8n
.It Cm promiscphys
Enable promiscuous mode at the physical level (default: false)
.It Cm promiscsap
Enable promiscuous mode at the SAP level (default: true)
.It Cm promiscmulti
Enable promiscuous mode for all multicast addresses (default: true)
.It Cm promiscrxonly
The selected promiscuous modes are only enabled for received traffic
(default: true).
.El
.Pp
.Sy Block storage device backends :
.Sm off
.Bl -bullet
.It
.Pa /filename Op Cm \&, Ar block-device-options
.It
.Pa /dev/xxx Op Cm \&, Ar block-device-options
.El
.Sm on
.Pp
The
.Ar block-device-options
are:
.Bl -tag -width 10n
.It Cm nocache
Open the file with
.Dv O_DIRECT .
.It Cm direct
Open the file using
.Dv O_SYNC .
.It Cm ro
Force the file to be opened read-only.
.It Cm sectorsize= Ns Ar logical Ns Oo Cm \&/ Ns Ar physical Oc
Specify the logical and physical sector sizes of the emulated disk.
The physical sector size is optional and is equal to the logical sector size
if not explicitly specified.
.It Cm nodelete
Disable emulation of guest trim requests via
.Dv DIOCGDELETE
requests.
.El
.Pp
.Sy 9P device backends :
.Sm off
.Bl -bullet
.It
.Ar sharename Cm = Ar /path/to/share Op Cm \&, Ar 9p-device-options
.El
.Sm on
.Pp
The
.Ar 9p-device-options
are:
.Bl -tag -width 10n
.It Cm ro
Expose the share in read-only mode.
.El
.Pp
.Sy TTY device backends :
.Bl -tag -width 10n
.It Cm stdio
Connect the serial port to the standard input and output of
the
.Nm
process.
.It Pa /dev/xxx
Use the host TTY device for serial port I/O.
.El
.Pp
.Sy Boot ROM device backends :
.Bl -tag -width 10n
.It Pa romfile Ns Op Cm \&, Ns Ar varfile
Map
.Ar romfile
in the guest address space reserved for boot firmware.
If
.Ar varfile
is provided, that file is also mapped in the boot firmware guest
address space, and any modifications the guest makes will be saved
to that file.
.El
.Pp
.Sy Pass-through device backends :
.Bl -tag -width 10n
.It Pa /dev/ppt Ns Ar N
Connect to a PCI device on the host identified by the specified path.
.It Cm rom= Ns Ar romfile
Add
.Ar romfile
as option ROM to the PCI device.
The ROM will be loaded by firmware and should be capable of initialising the
device.
.El
.Pp
Guest memory must be wired using the
.Fl S
option when a pass-through device is configured.
.Pp
The host device must have been previously attached to the
.Sy ppt
driver.
.Pp
.Sy Virtio console device backends :
.Bl -bullet
.Sm off
.It
.Cm port1= Ns Ar /path/to/port1.sock Ns
.Op Cm ,port Ns Ar N Cm \&= Ns Ar /path/to/port2.sock No \~ Ar ...
.Sm on
.El
.Pp
A maximum of 16 ports per device can be created.
Every port is named and corresponds to a UNIX domain socket created by
.Nm .
.Nm
accepts at most one connection per port at a time.
.Pp
Limitations:
.Bl -bullet
.It
Due to lack of destructors in
.Nm ,
sockets on the filesystem must be cleaned up manually after
.Nm
exits.
.It
There is no way to use the
.Dq console port
feature, nor the console port resize at present.
.It
Emergency write is advertised, but no-op at present.
.El
.Pp
.Sy Framebuffer device backends :
.Bl -bullet
.Sm off
.It
.Op Cm rfb= Ar ip-and-port
.Op Cm ,w= Ar width
.Op Cm ,h= Ar height
.Op Cm ,vga= Ar vgaconf
.Op Cm ,wait
.Op Cm ,password= Ar password
.Sm on
.El
.Pp
Configuration options are defined as follows:
.Bl -tag -width 10n
.It Cm rfb= Ns Ar ip-and-port Pq or Cm tcp= Ns Ar ip-and-port
An IP address and a port VNC should listen on.
There are two formats:
.Pp
.Bl -bullet -compact
.It
.Sm off
.Op Ar IPv4 Cm \&:
.Ar port
.Sm on
.It
.Sm off
.Cm \&[ Ar IPv6 Cm \&] Cm \&: Ar port
.Sm on
.El
.Pp
The default is to listen on localhost IPv4 address and default VNC port 5900.
An IPv6 address must be enclosed in square brackets.
.It Cm unix Ns = Ns Ar path
The path to a UNIX socket which will be created and where
.Nm
will accept VNC connections.
.It Cm w= Ns Ar width No and Cm h= Ns Ar height
A display resolution, width and height, respectively.
If not specified, a default resolution of 1024x768 pixels will be used.
Minimal supported resolution is 640x480 pixels,
and maximum is 1920x1200 pixels.
.It Cm vga= Ns Ar vgaconf
Possible values for this option are
.Cm io
(default),
.Cm on
, and
.Cm 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
.Pq Ad 0x3c0-3df
and memory space
.Pq 64KB at Ad 0xA0000 .
The default
.Cm 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 disabled.
.Pp
The
.Cm 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.
.Pp
The
.Cm 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
.Ox
in UEFI mode.
.It Cm wait
Instruct
.Nm
to only boot upon the initiation of a VNC connection, simplifying the
installation of operating systems that require immediate keyboard input.
This can be removed for post-installation use.
.It Cm password= Ns Ar password
This type of authentication is known to be cryptographically weak and is not
intended for use on untrusted networks.
Many implementations will want to use stronger security, such as running
the session over an encrypted channel provided by IPsec or SSH.
.El
.Pp
.Sy xHCI USB device backends :
.Bl -tag -width 10n
.It Cm tablet
A USB tablet device which provides precise cursor synchronization
when using VNC.
.El
.Pp
.Sy NVMe device backends :
.Bl -bullet
.Sm off
.It
.Ar devpath
.Op Cm ,maxq= Ar #
.Op Cm ,qsz= Ar #
.Op Cm ,ioslots= Ar #
.Op Cm ,sectsz= Ar #
.Op Cm ,ser= Ar #
.Op Cm ,eui64= Ar #
.Op Cm ,dsm= Ar opt
.Sm on
.El
.Pp
Configuration options are defined as follows:
.Bl -tag -width 10n
.It Ar devpath
Accepted device paths are:
.Ar /dev/blockdev
or
.Ar /path/to/image
or
.Cm ram= Ns Ar size_in_MiB .
.It Cm maxq
Max number of queues.
.It Cm qsz
Max elements in each queue.
.It Cm ioslots
Max number of concurrent I/O requests.
.It Cm sectsz
Sector size (defaults to blockif sector size).
.It Cm ser
Serial number with maximum 20 characters.
.It Cm eui64
IEEE Extended Unique Identifier (8 byte value).
.It Cm dsm
DataSet Management support.
Supported values are:
.Cm auto , enable ,
and
.Cm disable .
.El
.Pp
.Sy AHCI device backends :
.Bl -bullet
.It
.Sm off
.Op Oo Cm hd\&: | cd\&: Oc Ar path
.Op Cm ,nmrr= Ar nmrr
.Op Cm ,ser= Ar #
.Op Cm ,rev= Ar #
.Op Cm ,model= Ar #
.Sm on
.El
.Pp
Configuration options are defined as follows:
.Bl -tag -width 10n
.It Cm nmrr
Nominal Media Rotation Rate, known as RPM.
Value 1 will indicate device as Solid State Disk.
Default value is 0, not report.
.It Cm ser
Serial Number with maximum 20 characters.
.It Cm rev
Revision Number with maximum 8 characters.
.It Cm model
Model Number with maximum 40 characters.
.El
.It Fl U Ar uuid
Set the universally unique identifier
.Pq UUID
in the guest's System Management BIOS System Information structure.
By default a UUID is generated from the host's hostname and
.Ar vmname .
.It Fl u
RTC keeps UTC time.
.It Fl W
Force virtio PCI device emulations to use MSI interrupts instead of MSI-X
interrupts.
.It Fl w
Ignore accesses to unimplemented Model Specific Registers (MSRs).
This is intended for debug purposes.
.It Fl x
The guest's local APIC is configured in x2APIC mode.
.It Fl Y
Disable MPtable generation.
.It Ar vmname
Alphanumeric name of the guest.
.El
.Sh CONFIGURATION VARIABLES
.Nm
uses an internal tree of configuration variables to describe global and
per-device settings.
When
.Nm
starts,
it parses command line options (including config files) in the order given
on the command line.
Each command line option sets one or more configuration variables.
For example,
the
.Fl s
option creates a new tree node for a PCI device and sets one or more variables
under that node including the device model and device model-specific variables.
Variables may be set multiple times during this parsing stage with the final
value overriding previous values.
.Pp
Once all of the command line options have been processed,
the configuration values are frozen.
.Nm
then uses the value of configuration values to initialize device models
and global settings.
.Pp
More details on configuration variables can be found in
.Xr bhyve_config 5 .
.Sh SIGNAL HANDLING
.Nm
deals with the following signals:
.Pp
.Bl -tag -width SIGTERM -compact
.It SIGTERM
Trigger ACPI poweroff for a VM
.El
.Sh EXIT STATUS
Exit status indicates how the VM was terminated:
.Pp
.Bl -tag -width indent -compact
.It 0
rebooted
.It 1
powered off
.It 2
halted
.It 3
triple fault
.It 4
exited due to an error
.El
.Sh EXAMPLES
To run a virtual machine with 1GB of memory, two virtual CPUs, a virtio
block device backed by the
.Pa /my/image
filesystem image, and a serial port for the console:
.Bd -literal -offset indent
bhyve -c 2 -s 0,hostbridge -s 1,lpc -s 2,virtio-blk,/my/image \e
  -l com1,stdio -H -P -m 1G vm1
.Ed
.Pp
Run a 24GB single-CPU virtual machine with three network ports.
.Bd -literal -offset indent
bhyve -s 0,hostbridge -s 1,lpc -s 2:0,virtio-net-viona,vmvnic0 \e
  -s 2:1,virtio-net-viona,vmvnic1 -s 2:2,virtio-net-viona,vmvnic2 \e
  -s 3,virtio-blk,/my/image -l com1,stdio \e
  -H -P -m 24G bigvm
.Ed
.Pp
Run an 8GB virtual machine with 2 quad core CPUs, 2 NVMe disks and one other
disk attached as a Virtio block device, an AHCI ATAPI CD-ROM, a single viona
network port, an i440fx hostbridge, and the console port connected to a socket.
.Bd -literal -offset indent
bhyve -c sockets=2,cores=4,threads=2 \e
  -s 0,hostbridge,model=i440fx -s 1,lpc \e
  -s 1:0,nvme,/dev/zvol/rdsk/tank/hdd0 \e
  -s 1:1,nvme,/dev/zvol/rdsk/tank/hdd1 \e
  -s 1:2,virtio-blk,/dev/zvol/rdsk/tank/hdd1 \e
  -s 2:0,ahci,cd:/images/install.iso \e
  -s 3,virtio-net-viona,vnic=vmvnic0 \e
  -l com1,socket,/tmp/vm.com1,wait \e
  -H -P -m 8G
.Ed
.Pp
Run a UEFI virtual machine with a display resolution of 800 by 600 pixels
that can be accessed via VNC at: 0.0.0.0:5900.
.Bd -literal -offset indent
bhyve -c 2 -m 4G -w -H \e
  -s 0,hostbridge \e
  -s 3,ahci-cd,/path/to/uefi-OS-install.iso \e
  -s 4,nvme,/dev/zvol/rdsk/tank/hdd0 \e
  -s 5,virtio-net-viona,vnic=vnmic0 \e
  -s 29,fbuf,vga=off,rfb=0.0.0.0:5900,w=800,h=600,wait \e
  -s 30,xhci,tablet \e
  -s 31,lpc -l com1,stdio \e
  -l bootrom,/usr/share/bhyve/firmware/BHYVE_UEFI.fd \e
   uefivm
.Ed
.Pp
Run a UEFI virtual machine with a VARS file to save EFI variables.
Note that
.Nm
will write guest modifications to the given VARS file.
Be sure to create a per-guest copy of the template VARS file from
.Pa /usr/share/bhyve/firmware .
.Bd -literal -offset indent
bhyve -c 2 -m 4g -w -H \e
  -s 0,hostbridge \e
  -s 31,lpc -p com1,stdio \e
  -l bootrom,/usr/share/bhyve/firmware/BHYVE_UEFI.fd,BHYVE_UEFI_VARS.fd \e
   uefivm
.Ed
.Sh SEE ALSO
.Xr bhyve_config 5 ,
.Xr bhyvectl 8
.Pp
.Rs
.%A Intel
.%B 64 and IA-32 Architectures Software Developers' Manual
.%V Volume 3
.Re