xref: /freebsd/usr.sbin/bhyve/bhyve_config.5 (revision 924226fba12cc9a228c73b956e1b7fa24c60b055)
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26.Dd March 2, 2022
27.Dt BHYVE_CONFIG 5
28.Os
29.Sh NAME
30.Nm bhyve_config
31.Nd "bhyve configuration variables"
32.Sh DESCRIPTION
33.Xr bhyve 8
34uses a hierarchical tree of configuration variables to describe global and
35per-device settings.
36Internal nodes in this tree do not have a value,
37only leaf nodes have values.
38This manual describes the configuration variables understood by
39.Xr bhyve 8 .
40If additional variables are defined,
41.Xr bhyve 8
42will ignore them and will not emit errors for unknown variables.
43However, these additional variables can be referenced by other
44variables as described below.
45.Sh VARIABLE VALUES
46Configuration variable values are stored as strings.
47A configuration variable value may refer to one or more other
48configuration values by name.
49Instances of the pattern
50.Sq % Ns Pq Ar var
51are replaced by the value of the configuration variable
52.Va var .
53To avoid unwanted expansion,
54.Sq %
55characters can be escaped by a leading
56.Sq % .
57For example,
58if a configuration variable
59.Va disk
60uses the value
61.Pa /dev/zvol/bhyve/%(name) ,
62then the final value of the
63.Va disk
64variable will be set to the path of a ZFS volume whose name matches
65the name of the virtual machine on the pool
66.Pa bhyve .
67.Pp
68Some configuration variables may be interpreted as a boolean value.
69For those variables the following case-insensitive values may be used to
70indicate true:
71.Pp
72.Bl -bullet -offset indent -compact
73.It
74true
75.It
76on
77.It
78yes
79.It
801
81.El
82.Pp
83The following values may be used to indicate false:
84.Pp
85.Bl -bullet -offset indent -compact
86.It
87false
88.It
89off
90.It
91no
92.It
930
94.El
95.Pp
96Some configuration variables may be interperted as an integer.
97For those variables,
98any syntax supported by
99.Xr strtol 3
100may be used.
101.Sh GLOBAL SETTINGS
102.Ss Architecture Neutral Settings
103.Bl -column "memory.guest_in_core" "integer" "Default"
104.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
105.It Va name Ta string Ta Ta
106The name of the VM.
107.It Va cpus Ta integer Ta 1 Ta
108The total number of virtual CPUs.
109.It Va cores Ta integer Ta 1 Ta
110The number of virtual cores in each virtual socket.
111.It Va threads Ta integer Ta 1 Ta
112The number of virtual CPUs in each virtual core.
113.It Va sockets Ta integer Ta 1 Ta
114The number of virtual sockets.
115.It Va memory.guest_in_core Ta bool Ta false Ta
116Include guest memory in core file.
117.It Va memory.size Ta string Ta 256M Ta
118Guest physical memory size in bytes.
119The value must be formatted as described in
120.Xr expand_number 3 .
121.It Va memory.wired Ta bool Ta false Ta
122Wire guest memory.
123.It Va acpi_tables Ta bool Ta false Ta
124Generate ACPI tables.
125.It Va destroy_on_poweroff Ta bool Ta false Ta
126Destroy the VM on guest-initiated power-off.
127.It Va gdb.address Ta string Ta localhost Ta
128Hostname, IP address, or IPv6 address for the debug server.
129.It Va gdb.port Ta integer Ta 0 Ta
130TCP port number for the debug server.
131If this is set to a non-zero value, a debug server
132will listen for connections on this port.
133.It Va gdb.wait Ta bool Ta false Ta
134If the debug server is enabled, wait for a debugger to connect
135before starting the guest.
136.It Va keyboard.layout Ta string Ta Ta
137Specify the keyboard layout name with the file name in
138.Ar /usr/share/bhyve/kbdlayout .
139This value only works when loaded with UEFI mode for VNC, and
140used a VNC client that don't support QEMU Extended Key Event
141Message (e.g. TightVNC).
142.It Va rtc.use_localtime Ta bool Ta true Ta
143The real time clock uses the local time of the host.
144If this is set to false, the real time clock uses UTC.
145.It Va uuid Ta string Ta Ta
146The universally unique identifier (UUID) to use in the guest's
147System Management BIOS System Information structure.
148If an explicit value is not set, a valid UUID is generated from
149the host's hostname and the VM name.
150.It Va virtio_msix Ta bool Ta true Ta
151Use MSI-X interrupts for PCI VirtIO devices.
152If set to false, MSI interrupts are used instead.
153.It Va config.dump Ta bool Ta false Ta
154If this value is set to true after
155.Xr bhyve 8
156has finished parsing command line options,
157then
158.Xr bhyve 8
159will write all of its configuration variables to stdout and exit.
160No VM will be started.
161.It Va bios.vendor Ta string Ta BHYVE Ta
162This value is used for the guest's System Management BIOS System Information structure.
163.It Va bios.version Ta string Ta 14.0 Ta
164This value is used for the guest's System Management BIOS System Information structure.
165.It Va bios.release_date Ta string Ta 10/17/2021 Ta
166This value is used for the guest's System Management BIOS System Information structure.
167.It Va system.family_name Ta string Ta Virtual Machine Ta
168Family the computer belongs to.
169This value is used for the guest's System Management BIOS System Information structure.
170.It Va system.manufacturer Ta string Ta FreeBSD Ta
171This value is used for the guest's System Management BIOS System Information structure.
172.It Va system.product_name Ta string Ta BHYVE Ta
173This value is used for the guest's System Management BIOS System Information structure.
174.It Va system.serial_number Ta string Ta None Ta
175This value is used for the guest's System Management BIOS System Information structure.
176.It Va system.sku Ta string Ta None Ta
177Stock keeping unit of the computer.
178It's also called product ID or purchase order number.
179This value is used for the guest's System Management BIOS System Information structure.
180.It Va system.version Ta string Ta 1.0 Ta
181This value is used for the guest's System Management BIOS System Information structure.
182.It Va board.manufacturer Ta string Ta FreeBSD Ta
183This value is used for the guest's System Management BIOS System Information structure.
184.It Va board.product_name Ta string Ta BHYVE Ta
185This value is used for the guest's System Management BIOS System Information structure.
186.It Va board.version Ta string Ta 1.0 Ta
187This value is used for the guest's System Management BIOS System Information structure.
188.It Va board.serial_number Ta string Ta None Ta
189This value is used for the guest's System Management BIOS System Information structure.
190.It Va board.asset_tag Ta string Ta None Ta
191This value is used for the guest's System Management BIOS System Information structure.
192.It Va board.location Ta string Ta None Ta
193Describes the board's location within the chassis.
194This value is used for the guest's System Management BIOS System Information structure.
195.It Va chassis.manufacturer Ta string Ta FreeBSD Ta
196This value is used for the guest's System Management BIOS System Information structure.
197.It Va chassis.version Ta string Ta 1.0 Ta
198This value is used for the guest's System Management BIOS System Information structure.
199.It Va chassis.serial_number Ta string Ta None Ta
200This value is used for the guest's System Management BIOS System Information structure.
201.It Va chassis.asset_tag Ta string Ta None Ta
202This value is used for the guest's System Management BIOS System Information structure.
203.It Va chassis.sku Ta string Ta None Ta
204Stock keeping unit of the chassis.
205It's also called product ID or purchase order number.
206This value is used for the guest's System Management BIOS System Information structure.
207.El
208.Ss x86-Specific Settings
209.Bl -column "x86.vmexit_on_pause" "integer" "Default"
210.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
211.It Va x86.mptable Ta bool Ta true Ta
212Generate an MPTable.
213.It Va x86.x2apic Ta bool Ta false Ta
214Configure guest's local APICs in x2APIC mode.
215.It Va x86.strictio Ta bool Ta false Ta
216Exit if a guest accesses an I/O port that is not emulated.
217By default, writes are ignored and reads return all bits set.
218.It Va x86.strictmsr Ta bool Ta true Ta
219Inject a general protection fault if a guest accesses a Model Specific
220Register (MSR) that is not emulated.
221If this is false, writes are ignored and reads return zero.
222.It Va x86.vmexit_on_hlt Ta bool Ta false Ta
223Force a VM exit when a guest CPU executes the
224.Dv HLT
225instruction.
226This allows idle guest CPUs to yield the host CPU.
227.It Va x86.vmexit_on_pause Ta bool Ta false Ta
228Force a VM exit when a guest CPU executes the
229.Dv PAUSE
230instruction.
231.El
232.Sh DEVICE SETTINGS
233Device settings are stored under a device node.
234The device node's name is set by the parent bus of the device.
235.Ss PCI Device Settings
236PCI devices are described by a device node named
237.Dq pci . Ns Ar bus . Ns Ar slot . Ns Ar function
238where each of
239.Ar bus ,
240.Ar slot ,
241and
242.Ar function
243are formatted as decimal values with no padding.
244All PCI device nodes must contain a configuration variable named
245.Dq device
246which specifies the device model to use.
247The following PCI device models are supported:
248.Bl -tag -indent
249.It Li hostbridge
250Provide a simple PCI-Host bridge device.
251This is usually configured at pci0:0:0 and is required by most guest
252operating systems.
253.It Li ahci
254AHCI storage controller.
255.It Li e1000
256Intel e82545 network interface.
257.It Li fbuf
258VGA framebuffer device attached to VNC server.
259.It Li lpc
260LPC PCI-ISA bridge with COM1-COM4 16550 serial ports,
261a boot ROM,
262and an optional debug/test device.
263This device must be configured on bus 0.
264.It Li hda
265High Definition audio controller.
266.It Li nvme
267NVM Express (NVMe) controller.
268.It Li passthru
269PCI pass-through device.
270.It Li uart
271PCI 16550 serial device.
272.It Li virtio-9p
273VirtIO 9p (VirtFS) interface.
274.It Li virtio-blk
275VirtIO block storage interface.
276.It Li virtio-console
277VirtIO console interface.
278.It Li virtio-input
279VirtIO input interface.
280.It Li virtio-net
281VirtIO network interface.
282.It Li virtio-rnd
283VirtIO RNG interface.
284.It Li virtio-scsi
285VirtIO SCSI interface.
286.It Li xhci
287Extensible Host Controller Interface (XHCI) USB controller.
288.El
289.Ss USB Device Settings
290USB controller devices contain zero or more child USB devices
291attached to slots.
292Each USB device stores its settings in a node named
293.Dq slot. Ns Va N
294under the controller's device node.
295.Va N
296is the number of the slot to which the USB device is attached.
297Note that USB slot numbers begin at 1.
298All USB device nodes must contain a configuration variable named
299.Dq device
300which specifies the device model to use.
301The following USB device models are supported:
302.Bl -tag -indent
303.It Li tablet
304A USB tablet device which provides precise cursor synchronization
305when using VNC.
306.El
307.Ss Block Device Settings
308Block devices use the following settings to configure their backing store.
309These settings are stored in the configuration node of the respective device.
310.Bl -column "sectorsize" "logical[/physical]" "Default"
311.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
312.It path Ta string Ta Ta
313The path of the file or disk device to use as the backing store.
314.It nocache Ta bool Ta false Ta
315Disable caching on the backing file by opening the backing file with
316.Dv O_DIRECT .
317.It nodelete Ta bool Ta false Ta
318Disable emulation of guest trim requests via
319.Dv DIOCGDELETE
320requests.
321.It sync Ta bool Ta false Ta
322Write changes to the backing file with synchronous writes.
323.It direct Ta bool Ta false Ta
324An alias for
325.Va sync .
326.It ro Ta bool Ta false Ta
327Disable writes to the backing file.
328.It sectorsize Ta Va logical Ns Op / Ns Va physical Ta Ta
329Specify the logical and physical sector size of the emulated disk.
330If the physical size is not specified,
331it is equal to the logical size.
332.El
333.Ss Network Backend Settings
334Network devices use the following settings to configure their backend.
335The backend is responsible for passing packets between the device model
336and a desired destination.
337Configuring a backend requires setting the
338.Va backend
339variable to one of the following values:
340.Bl -tag
341.It tap Ns Va N
342Use the named
343.Xr tap 4
344interface as the backend.
345.It vmnet Ns Va N
346Use the named
347.Xr vmnet 4
348interface as the backend.
349.It netgraph
350Use a
351.Xr netgraph 4
352socket hook as the backend.
353This backend uses the following additional variables:
354.Bl -column "peerhook" "Format" "Default"
355.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
356.It Va path Ta string Ta Ta
357The name of the
358.Xr netgraph 4
359destination node.
360.It Va peerhook Ta string Ta Ta
361The name of the destination hook.
362.It Va socket Ta string Ta Ta
363The name of the created
364.Xr ng_socket 4
365node.
366.It Va hook Ta string Ta vmlink Ta
367The name of the source hook on the created
368.Xr ng_socket 4
369node.
370.El
371.It netmap: Ns Va interface
372Use
373.Xr netmap 4
374on a network interface as the backend.
375.It vale Ns Va bridge : Ns Va port
376Use a port on a
377.Xr vale 4
378bridge as the backend.
379.El
380.Ss UART Device Settings
381.Bl -column "Name" "Format" "Default"
382.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
383.It Va path Ta path Ta Ta
384Backend device for the serial port.
385Either the pathname of a character device or
386.Dq stdio
387to use standard input and output of the
388.Xr bhyve 8
389process.
390.El
391.Ss Host Bridge Settings
392.Bl -column "vendor" "integer" "Default"
393.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
394.It Va vendor Ta integer Ta 0x1275 Ta
395PCI vendor ID.
396.It Va devid Ta integer Ta 0x1275 Ta
397PCI device ID.
398.El
399.Ss AHCI Controller Settings
400AHCI controller devices contain zero or more ports each of which
401provides a storage device.
402Each port stores its settings in a node named
403.Dq port. Ns Va N
404under the controller's device node.
405The
406.Va N
407values are formatted as successive decimal values starting with 0.
408In addition to the block device settings described above, each
409port supports the following settings:
410.Bl -column "model" "integer" "generated"
411.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
412.It Va type Ta string Ta Ta
413The type of storage device to emulate.
414Must be set to either
415.Dq cd
416or
417.Dq hd .
418.It Va nmrr Ta integer Ta 0 Ta
419Nominal Media Rotation Rate, also known as RPM.
420A value 1 of indicates a device with no rate such as a Solid State Disk.
421.It Va ser Ta string Ta generated Ta
422Serial number of up to twenty characters.
423A default serial number is generated using a hash of the backing
424store's pathname.
425.It Va rev Ta string Ta 001 Ta
426Revision number of up to eight characters.
427.It Va model Ta string Ta Ta
428Model number of up to forty characters.
429Separate default model strings are used for
430.Dq cd
431and
432.Dq hd
433device types.
434.El
435.Ss e1000 Settings
436In addition to the network backend settings,
437Intel e82545 network interfaces support the following variables:
438.Bl -column "Name" "MAC address" "generated"
439.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
440.It Va mac Ta MAC address Ta generated Ta
441MAC address.
442If an explicit address is not provided,
443a MAC address is generated from a hash of the device's PCI address.
444.El
445.Ss Frame Buffer Settings
446.Bl -column "password" "[IP:]port" "127.0.0.1:5900"
447.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
448.It Va wait Ta bool Ta false Ta
449Wait for a remote connection before starting the VM.
450.It Va rfb Ta Oo Ar IP Ns : Oc Ns Ar port Ta 127.0.0.1:5900 Ta
451TCP address to listen on for remote connections.
452The IP address must be given as a numeric address.
453IPv6 addresses must be enclosed in square brackets and
454support scoped identifiers as described in
455.Xr getaddrinfo 3 .
456A bare port number may be given in which case the IPv4
457localhost address is used.
458.It Va vga Ta string Ta io Ta
459VGA configuration.
460More details are provided in
461.Xr bhyve 8 .
462.It Va w Ta integer Ta 1024 Ta
463Frame buffer width in pixels.
464.It Va h Ta integer Ta 768 Ta
465Frame buffer height in pixels.
466.It Va password Ta string Ta Ta
467Password to use for VNC authentication.
468This type of authentication is known to be cryptographically weak and is not
469intended for use on untrusted networks.
470.El
471.Ss High Definition Audio Settings
472.Bl -column "Name" "Format" "Default"
473.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
474.It Va play Ta path Ta Ta
475Host playback device,
476typically
477.Pa /dev/dsp0 .
478.It Va rec Ta path Ta Ta
479Host recording device,
480typically
481.Pa /dev/dsp0 .
482.El
483.Ss LPC Device Settings
484The LPC bridge stores its configuration under a top-level
485.Va lpc
486node rather than under the PCI LPC device's node.
487The following nodes are available under
488.Va lpc :
489.Bl -column "pc-testdev" "Format" "Default"
490.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
491.It Va bootrom Ta path Ta Ta
492Path to a boot ROM.
493The contents of this file are copied into the guest's
494memory ending just before the 4GB physical address.
495If a boot ROM is present, a firmware interface device is
496also enabled for use by the boot ROM.
497.It Va bootvars Ta path Ta Ta
498Path to boot VARS.
499The contents of this file are copied beneath the boot ROM.
500Firmware can write to it to save variables.
501All variables will be persistent even on reboots of the guest.
502.It Va com1 Ta node Ta Ta
503Settings for the COM1 serial port device.
504.It Va com2 Ta node Ta Ta
505Settings for the COM2 serial port device.
506.It Va com3 Ta node Ta Ta
507Settings for the COM3 serial port device.
508.It Va com4 Ta node Ta Ta
509Settings for the COM4 serial port device.
510.It Va pc-testdev Ta bool Ta false Ta
511Enable the PC debug/test device.
512.El
513.Ss NVMe Controller Settings
514Each NVMe controller supports a single storage device.
515The device can be backed either by a memory disk described by the
516.Va ram
517variable, or a block device using the block device settings described above.
518In addition, each controller supports the following settings:
519.Bl -column "ioslots" "Format" "Default"
520.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
521.It Va maxq Ta integer Ta 16 Ta
522Maximum number of I/O submission and completion queue pairs.
523.It Va qsz Ta integer Ta 2058 Ta
524Number of elements in each I/O queue.
525.It Va ioslots Ta integer Ta 8 Ta
526Maximum number of concurrent I/O requests.
527.It Va sectsz Ta integer Ta Ta
528Sector size.
529Can be one of 512, 4096, or 8192.
530Devices backed by a memory disk use 4096 as the default.
531Devices backed by a block device use the block device's sector size
532as the default.
533.It Va ser Ta string Ta Ta
534Serial number of up to twenty characters.
535A default serial number is generated using a hash of the device's PCI address.
536.It Va eui64 Ta integer Ta Ta
537IEEE Extended Unique Identifier.
538If an EUI is not provided, a default is generated using a checksum of the
539device's PCI address.
540.It Va dsm Ta string Ta auto Ta
541Whether or not to advertise DataSet Management support.
542One of
543.Dq auto ,
544.Dq enable ,
545or
546.Dq disable .
547The
548.Dq auto
549setting only advertises support if the backing store supports
550resource freeing, for example via TRIM.
551.It Va ram Ta integer Ta Ta
552If set, allocate a memory disk as the backing store.
553The value of this variable is the size of the memory disk in megabytes.
554.El
555.Ss PCI Passthrough Settings
556.Bl -column "Name" "integer" "Default"
557.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
558.It Va bus Ta integer Ta Ta
559Host PCI bus address of device to pass through.
560.It Va slot Ta integer Ta Ta
561Host PCI slot address of device to pass through.
562.It Va func Ta integer Ta Ta
563Host PCI function address of device to pass through.
564.It Va rom Ta path Ta Ta
565ROM file of the device which will be executed by OVMF to init the device.
566.El
567.Ss VirtIO 9p Settings
568Each VirtIO 9p device exposes a single filesystem from a host path.
569.Bl -column "sharename" "Format" "Default"
570.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
571.It Va sharename Ta string Ta Ta
572The share name exposed to the guest.
573.It Va path Ta path Ta Ta
574The path of a directory on the host to export to the guest.
575.It Va ro Ta bool Ta false Ta
576If true, the guest filesystem is read-only.
577.El
578.Ss VirtIO Block Device Settings
579In addition to the block device settings described above, each
580VirtIO block device supports the following settings:
581.Bl -column "model" "integer" "generated"
582.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
583.It Va ser Ta string Ta generated Ta
584Serial number of up to twenty characters.
585A default serial number is generated using a hash of the backing
586store's pathname.
587.El
588.Ss VirtIO Console Device Settings
589Each VirtIO Console device contains one or more console ports.
590Each port stores its settings in a node named
591.Dq port. Ns Va N
592under the controller's device node.
593The
594.Va N
595values are formatted as successive decimal values starting with 0.
596Each port supports the following settings:
597.Bl -column "Name" "Format" "Default"
598.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
599.It Va name Ta string Ta Ta
600The name of the port exposed to the guest.
601.It Va path Ta path Ta Ta
602The path of a UNIX domain socket providing the host connection for the port.
603.El
604.Ss VirtIO Input Interface Settings
605Each VirtIO Input device contains one input event device.
606All input events of the input event device are send to the guest by VirtIO Input interface.
607VirtIO Input Interfaces support the following variables:
608.Bl -column "Name" "Format" "Default"
609.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
610.It Va path Ta path Ta Ta
611The path of the input event device exposed to the guest
612.El
613.Ss VirtIO Network Interface Settings
614In addition to the network backend settings,
615VirtIO network interfaces support the following variables:
616.Bl -column "Name" "MAC address" "generated"
617.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
618.It Va mac Ta MAC address Ta generated Ta
619MAC address.
620If an explicit address is not provided,
621a MAC address is generated from a hash of the device's PCI address.
622.It Va mtu Ta integer Ta 1500 Ta
623The largest supported MTU advertised to the guest.
624.El
625.Ss VirtIO SCSI Settings
626.Bl -column "Name" "integer" "Default"
627.It Sy Name Ta Sy Format Ta Sy Default Ta Sy Description
628.It Va dev Ta path Ta Ta
629The path of a CAM target layer (CTL) device to export:
630.Pa /dev/cam/ctl Ns Oo Ar pp . Ns Ar vp Oc .
631.It Va iid Ta integer Ta 0 Ta
632Initiator ID to use when sending requests to the CTL port.
633.El
634.Sh SEE ALSO
635.Xr expand_number 3 ,
636.Xr getaddrinfo 3 ,
637.Xr strtol 3 ,
638.Xr netgraph 4 ,
639.Xr netmap 4 ,
640.Xr ng_socket 4 ,
641.Xr tap 4 ,
642.Xr vale 4 ,
643.Xr vmnet 4 ,
644.Xr bhyve 8
645