xref: /freebsd/usr.sbin/bhyve/bhyve.8 (revision d746ab215cc85d8f7ab05c5f866c338782c390ec)
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25.\" $FreeBSD$
26.\"
27.Dd November 28, 2021
28.Dt BHYVE 8
29.Os
30.Sh NAME
31.Nm bhyve
32.Nd "run a guest operating system inside a virtual machine"
33.Sh SYNOPSIS
34.Nm
35.Op Fl AaCDeHhPSuWwxY
36.Oo
37.Sm off
38.Fl c\~
39.Oo
40.Op Cm cpus=
41.Ar numcpus
42.Oc
43.Op Cm ,sockets= Ar n
44.Op Cm ,cores= Ar n
45.Op Cm ,threads= Ar n
46.Oc
47.Sm on
48.Oo
49.Sm off
50.Fl G\~
51.Oo Ar w Oc
52.Oo Ar bind_address Cm \&: Oc
53.Ar port
54.Sm on
55.Oc
56.Op Fl k Ar config_file
57.Op Fl K Ar layout
58.Oo Fl l
59.Sm off
60.Ar lpcdev Op Cm \&, Ar conf
61.Sm on
62.Oc
63.Sm off
64.Oo Fl m\~
65.Ar memsize
66.Oo
67.Cm K | Cm k | Cm M | Cm m | Cm G | Cm g | Cm T | Cm t
68.Oc
69.Sm on
70.Oc
71.Op Fl o Ar var Ns Cm = Ns Ar value
72.Op Fl p Ar vcpu Ns Cm \&: Ns Ar hostcpu
73.Op Fl r Ar file
74.Sm off
75.Oo Fl s\~
76.Ar slot Cm \&, Ar emulation Op Cm \&, Ar conf
77.Sm on
78.Oc
79.Op Fl U Ar uuid
80.Ar vmname
81.Nm
82.Fl l Cm help
83.Nm
84.Fl s Cm help
85.Sh DESCRIPTION
86.Nm
87is a hypervisor that runs guest operating systems inside a
88virtual machine.
89.Pp
90Parameters such as the number of virtual CPUs, amount of guest memory, and
91I/O connectivity can be specified with command-line parameters.
92.Pp
93If not using a boot ROM, the guest operating system must be loaded with
94.Xr bhyveload 8
95or a similar boot loader before running
96.Nm ,
97otherwise, it is enough to run
98.Nm
99with a boot ROM of choice.
100.Pp
101.Nm
102runs until the guest operating system reboots or an unhandled hypervisor
103exit is detected.
104.Sh OPTIONS
105.Bl -tag -width 10n
106.It Fl A
107Generate ACPI tables.
108Required for
109.Fx Ns /amd64
110guests.
111.It Fl a
112The guest's local APIC is configured in xAPIC mode.
113The xAPIC mode is the default setting so this option is redundant.
114It will be deprecated in a future version.
115.It Fl C
116Include guest memory in core file.
117.It Fl c Op Ar setting ...
118Number of guest virtual CPUs
119and/or the CPU topology.
120The default value for each of
121.Ar numcpus ,
122.Ar sockets ,
123.Ar cores ,
124and
125.Ar threads
126is 1.
127The current maximum number of guest virtual CPUs is 16.
128If
129.Ar numcpus
130is not specified then it will be calculated from the other arguments.
131The topology must be consistent in that the
132.Ar numcpus
133must equal the product of
134.Ar sockets ,
135.Ar cores ,
136and
137.Ar threads .
138If a
139.Ar setting
140is specified more than once the last one has precedence.
141.It Fl D
142Destroy the VM on guest initiated power-off.
143.It Fl e
144Force
145.Nm
146to exit when a guest issues an access to an I/O port that is not emulated.
147This is intended for debug purposes.
148.It Fl G Xo
149.Sm off
150.Oo Ar w Oc
151.Oo Ar bind_address Cm \&: Oc
152.Ar port
153.Sm on
154.Xc
155Start a debug server that uses the GDB protocol to export guest state to a
156debugger.
157An IPv4 TCP socket will be bound to the supplied
158.Ar bind_address
159and
160.Ar port
161to listen for debugger connections.
162Only a single debugger may be attached to the debug server at a time.
163If the option begins with
164.Sq w ,
165.Nm
166will pause execution at the first instruction waiting for a debugger to attach.
167.It Fl H
168Yield the virtual CPU thread when a HLT instruction is detected.
169If this option is not specified, virtual CPUs will use 100% of a host CPU.
170.It Fl h
171Print help message and exit.
172.It Fl k Ar config_file
173Set configuration variables from a simple, key-value config file.
174Each line of the config file is expected to consist of a config variable
175name, an equals sign
176.It Fl K Ar layout
177Specify the keyboard layout.
178The value that can be specified sets the file name in
179.Ar /usr/share/bhyve/kbdlayout .
180This specification only works when loaded with UEFI mode for VNC.
181When using a VNC client that supports QEMU Extended Key Event Message (e.g. TigerVNC), this option isn't needed.
182When using a VNC client that doesn't support QEMU Extended Key Event Message (e.g. tightVNC), the layout defaults to the US keyboard unless specified otherwise.
183.Pq Sq = ,
184and a value.
185No spaces are permitted between the variable name, equals sign, or
186value.
187Blank lines and lines starting with
188.Sq #
189are ignored.
190See
191.Xr bhyve_config 5
192for more details.
193.It Fl l Cm help
194Print a list of supported LPC devices.
195.It Fl l Ar lpcdev Ns Op Cm \&, Ns Ar conf
196Allow devices behind the LPC PCI-ISA bridge to be configured.
197The only supported devices are the TTY-class devices
198.Cm com1 , com2 , com3 ,
199and
200.Cm com4 ,
201the boot ROM device
202.Cm bootrom ,
203and the debug/test device
204.Cm pc-testdev .
205.Pp
206The possible values for the
207.Ar conf
208argument are listed in the
209.Fl s
210flag description.
211.It Xo
212.Fl m Ar memsize Ns Oo
213.Sm off
214.Cm K | k | M | m | G | g | T | t
215.Sm on
216.Oc
217.Xc
218Set the guest physical memory size
219This must be the same size that was given to
220.Xr bhyveload 8 .
221.Pp
222The size argument may be suffixed with one of
223.Cm K , M , G
224or
225.Cm T
226(either upper or lower case)
227to indicate a multiple of kilobytes, megabytes, gigabytes, or terabytes.
228If no suffix is given, the value is assumed to be in megabytes.
229.Pp
230The default is 256M.
231.It Fl o Ar var Ns Cm = Ns Ar value
232Set the configuration variable
233.Ar var
234to
235.Ar value .
236.It Fl P
237Force the guest virtual CPU to exit when a PAUSE instruction is detected.
238.It Fl p Ar vcpu Ns Cm \& : Ns Ar hostcpu
239Pin guest's virtual CPU
240.Em vcpu
241to
242.Em hostcpu .
243.It Fl r Ar file
244Resume a guest from a snapshot.
245The guest memory contents are restored from
246.Ar file ,
247and the guest device and vCPU state are restored from the file
248.Dq Ar file Ns .kern .
249.Pp
250Note that the current snapshot file format requires that the configuration of
251devices in the new VM match the VM from which the snapshot was taken by specifying the
252same
253.Fl s
254and
255.Fl l
256options.
257The count of vCPUs and memory configuration are read from the snapshot.
258.It Fl S
259Wire guest memory.
260.It Fl s Cm help
261Print a list of supported PCI devices.
262.It Fl s Ar slot Ns Cm \&, Ns Ar emulation Ns Op Cm \&, Ns Ar conf
263Configure a virtual PCI slot and function.
264.Pp
265.Nm
266provides PCI bus emulation and virtual devices that can be attached to
267slots on the bus.
268There are 32 available slots, with the option of providing up to 8 functions
269per slot.
270.Pp
271The
272.Ar slot
273can be specified in one of the following formats:
274.Pp
275.Bl -bullet -compact
276.It
277.Ar pcislot
278.It
279.Sm off
280.Ar pcislot Cm \&: Ar function
281.Sm on
282.It
283.Sm off
284.Ar bus Cm \&: Ar pcislot Cm \&: Ar function
285.Sm on
286.El
287.Pp
288The
289.Ar pcislot
290value is 0 to 31.
291The optional
292.Ar function
293value is 0 to 7.
294The optional
295.Ar bus
296value is 0 to 255.
297If not specified, the
298.Ar function
299value defaults to 0.
300If not specified, the
301.Ar bus
302value defaults to 0.
303.Pp
304The
305.Ar emulation
306argument
307can be one of the following:
308.Bl -tag -width "amd_hostbridge"
309.It Cm hostbridge
310A simple host bridge.
311This is usually configured at slot 0, and is required by most guest
312operating systems.
313.It Cm amd_hostbridge
314Emulation identical to
315.Cm hostbridge
316using a PCI vendor ID of AMD.
317.It Cm passthru
318PCI pass-through device.
319.It Cm virtio-net
320Virtio network interface.
321.It Cm virtio-blk
322Virtio block storage interface.
323.It Cm virtio-scsi
324Virtio SCSI interface.
325.It Cm virtio-9p
326Virtio 9p (VirtFS) interface.
327.It Cm virtio-rnd
328Virtio RNG interface.
329.It Cm virtio-console
330Virtio console interface, which exposes multiple ports
331to the guest in the form of simple char devices for simple IO
332between the guest and host userspaces.
333.It Cm virtio-input
334Virtio input interface.
335.It Cm ahci
336AHCI controller attached to arbitrary devices.
337.It Cm ahci-cd
338AHCI controller attached to an ATAPI CD/DVD.
339.It Cm ahci-hd
340AHCI controller attached to a SATA hard drive.
341.It Cm e1000
342Intel e82545 network interface.
343.It Cm uart
344PCI 16550 serial device.
345.It Cm lpc
346LPC PCI-ISA bridge with COM1, COM2, COM3, and COM4 16550 serial ports,
347a boot ROM, and,
348optionally, the debug/test device.
349The LPC bridge emulation can only be configured on bus 0.
350.It Cm fbuf
351Raw framebuffer device attached to VNC server.
352.It Cm xhci
353eXtensible Host Controller Interface (xHCI) USB controller.
354.It Cm nvme
355NVM Express (NVMe) controller.
356.It Cm hda
357High Definition Audio Controller.
358.El
359.Pp
360The optional parameter
361.Ar conf
362describes the backend for device emulations.
363If
364.Ar conf
365is not specified, the device emulation has no backend and can be
366considered unconnected.
367.Pp
368Network device backends:
369.Sm off
370.Bl -bullet
371.It
372.Xo
373.Cm tap Ar N
374.Op Cm \&,mac= Ar xx:xx:xx:xx:xx:xx
375.Op Cm \&,mtu= Ar N
376.Xc
377.It
378.Xo
379.Cm vmnet Ar N
380.Op Cm \&,mac= Ar xx:xx:xx:xx:xx:xx
381.Op Cm \&,mtu= Ar N
382.Xc
383.It
384.Xo
385.Cm netgraph,path= Ar ADDRESS Cm \&,peerhook= Ar HOOK
386.Op Cm \&,socket= Ar NAME
387.Op Cm \&,hook= Ar HOOK
388.Op Cm \&,mac= Ar xx:xx:xx:xx:xx:xx
389.Op Cm \&,mtu= Ar N
390.Xc
391.El
392.Sm on
393If
394.Cm mac
395is not specified, the MAC address is derived from a fixed OUI and the
396remaining bytes from an MD5 hash of the slot and function numbers and
397the device name.
398.Pp
399The MAC address is an ASCII string in
400.Xr ethers 5
401format.
402.Pp
403With
404.Cm virtio-net
405devices, the
406.Cm mtu
407parameter can be specified to inform the guest about the largest MTU
408that should be allowed, expressed in bytes.
409.Pp
410With
411.Cm netgraph
412backend, the
413.Cm path
414and
415.Cm peerhook
416parameters must be specified to set the destination node and corresponding hook.
417The optional parameters
418.Cm socket
419and
420.Cm hook
421may be used to set the
422.Xr ng_socket 4
423node name and source hook.
424The
425.Ar ADDRESS ,
426.Ar HOOK ,
427and
428.Ar NAME
429must comply with
430.Xr netgraph 4
431addressing rules.
432.Pp
433Block storage device backends:
434.Sm off
435.Bl -bullet
436.It
437.Ar /filename Op Cm \&, Ar block-device-options
438.It
439.Ar /dev/xxx Op Cm \&, Ar block-device-options
440.El
441.Sm on
442.Pp
443The
444.Ar block-device-options
445are:
446.Bl -tag -width 10n
447.It Cm nocache
448Open the file with
449.Dv O_DIRECT .
450.It Cm direct
451Open the file using
452.Dv O_SYNC .
453.It Cm ro
454Force the file to be opened read-only.
455.It Cm sectorsize= Ns Ar logical Ns Oo Cm \&/ Ns Ar physical Oc
456Specify the logical and physical sector sizes of the emulated disk.
457The physical sector size is optional and is equal to the logical sector size
458if not explicitly specified.
459.It Cm nodelete
460Disable emulation of guest trim requests via
461.Dv DIOCGDELETE
462requests.
463.El
464.Pp
465SCSI device backends:
466.Sm off
467.Bl -bullet
468.It
469.Pa /dev/cam/ctl Oo Ar pp Cm \&. Ar vp Oc Oo Cm \&, Ar scsi-device-options Oc
470.El
471.Sm on
472.Pp
473The
474.Ar scsi-device-options
475are:
476.Bl -tag -width 10n
477.It Cm iid= Ns Ar IID
478Initiator ID to use when sending requests to specified CTL port.
479The default value is 0.
480.El
481.Pp
4829P device backends:
483.Sm off
484.Bl -bullet
485.It
486.Ar sharename Cm = Ar /path/to/share Op Cm \&, Ar 9p-device-options
487.El
488.Sm on
489.Pp
490The
491.Ar 9p-device-options
492are:
493.Bl -tag -width 10n
494.It Cm ro
495Expose the share in read-only mode.
496.El
497.Pp
498TTY device backends:
499.Bl -tag -width 10n
500.It Cm stdio
501Connect the serial port to the standard input and output of
502the
503.Nm
504process.
505.It Ar /dev/xxx
506Use the host TTY device for serial port I/O.
507.El
508.Pp
509Boot ROM device backends:
510.Bl -tag -width 10n
511.It Ar romfile Ns Op Cm \&, Ns Ar varfile
512Map
513.Ar romfile
514in the guest address space reserved for boot firmware.
515If
516.Ar varfile
517is provided, that file is also mapped in the boot firmware guest
518address space, and any modifications the guest makes will be saved
519to that file.
520.El
521.Pp
522Pass-through device backends:
523.Bl -tag -width 10n
524.It Ns Ar slot Ns Cm \&/ Ns Ar bus Ns Cm \&/ Ns Ar function
525Connect to a PCI device on the host at the selector described by
526.Ar slot ,
527.Ar bus ,
528and
529.Ar function
530numbers.
531.El
532.Pp
533Guest memory must be wired using the
534.Fl S
535option when a pass-through device is configured.
536.Pp
537The host device must have been reserved at boot-time using the
538.Va pptdevs
539loader variable as described in
540.Xr vmm 4 .
541.Pp
542Virtio console device backends:
543.Bl -bullet
544.Sm off
545.It
546.Cm port1= Ns Ar /path/to/port1.sock Ns Op Cm ,port Ns Ar N Cm \&= Ns Ar /path/to/port2.sock No \~ Ar ...
547.Sm on
548.El
549.Pp
550A maximum of 16 ports per device can be created.
551Every port is named and corresponds to a Unix domain socket created by
552.Nm .
553.Nm
554accepts at most one connection per port at a time.
555.Pp
556Limitations:
557.Bl -bullet
558.It
559Due to lack of destructors in
560.Nm ,
561sockets on the filesystem must be cleaned up manually after
562.Nm
563exits.
564.It
565There is no way to use the
566.Dq console port
567feature, nor the console port
568resize at present.
569.It
570Emergency write is advertised, but no-op at present.
571.El
572.Pp
573Virtio input device backends:
574.Bl -tag -width 10n
575.It Ar /dev/input/eventX
576Send input events of
577.Ar /dev/input/eventX
578to guest by VirtIO Input Interface.
579.El
580.Pp
581Framebuffer devices backends:
582.Bl -bullet
583.Sm off
584.It
585.Op Cm rfb= Ar ip-and-port
586.Op Cm ,w= Ar width
587.Op Cm ,h= Ar height
588.Op Cm ,vga= Ar vgaconf
589.Op Cm ,wait
590.Op Cm ,password= Ar password
591.Sm on
592.El
593.Pp
594Configuration options are defined as follows:
595.Bl -tag -width 10n
596.It Cm rfb= Ns Ar ip-and-port Pq or Cm tcp= Ns Ar ip-and-port
597An IP address and a port VNC should listen on.
598There are two formats:
599.Pp
600.Bl -bullet -compact
601.It
602.Sm off
603.Op Ar IPv4 Cm \&:
604.Ar port
605.Sm on
606.It
607.Sm off
608.Cm \&[ Ar IPv6%zone Cm \&] Cm \&: Ar port
609.Sm on
610.El
611.Pp
612The default is to listen on localhost IPv4 address and default VNC port 5900.
613An IPv6 address must be enclosed in square brackets and may contain an
614optional zone identifier.
615.It Cm w= Ns Ar width No and Cm h= Ns Ar height
616A display resolution, width and height, respectively.
617If not specified, a default resolution of 1024x768 pixels will be used.
618Minimal supported resolution is 640x480 pixels,
619and maximum is 1920x1200 pixels.
620.It Cm vga= Ns Ar vgaconf
621Possible values for this option are
622.Cm io
623(default),
624.Cm on
625, and
626.Cm off .
627PCI graphics cards have a dual personality in that they are
628standard PCI devices with BAR addressing, but may also
629implicitly decode legacy VGA I/O space
630.Pq Ad 0x3c0-3df
631and memory space
632.Pq 64KB at Ad 0xA0000 .
633The default
634.Cm io
635option should be used for guests that attempt to issue BIOS calls which result
636in I/O port queries, and fail to boot if I/O decode is disabled.
637.Pp
638The
639.Cm on
640option should be used along with the CSM BIOS capability in UEFI
641to boot traditional BIOS guests that require the legacy VGA I/O and
642memory regions to be available.
643.Pp
644The
645.Cm off
646option should be used for the UEFI guests that assume that
647VGA adapter is present if they detect the I/O ports.
648An example of such a guest is
649.Ox
650in UEFI mode.
651.Pp
652Please refer to the
653.Nm
654.Fx
655wiki page
656.Pq Lk https://wiki.freebsd.org/bhyve
657for configuration notes of particular guests.
658.It Cm wait
659Instruct
660.Nm
661to only boot upon the initiation of a VNC connection, simplifying the
662installation of operating systems that require immediate keyboard input.
663This can be removed for post-installation use.
664.It Cm password= Ns Ar password
665This type of authentication is known to be cryptographically weak and is not
666intended for use on untrusted networks.
667Many implementations will want to use stronger security, such as running
668the session over an encrypted channel provided by IPsec or SSH.
669.El
670.Pp
671xHCI USB device backends:
672.Bl -tag -width 10n
673.It Cm tablet
674A USB tablet device which provides precise cursor synchronization
675when using VNC.
676.El
677.Pp
678NVMe device backends:
679.Bl -bullet
680.Sm off
681.It
682.Ar devpath
683.Op Cm ,maxq= Ar #
684.Op Cm ,qsz= Ar #
685.Op Cm ,ioslots= Ar #
686.Op Cm ,sectsz= Ar #
687.Op Cm ,ser= Ar #
688.Op Cm ,eui64= Ar #
689.Op Cm ,dsm= Ar opt
690.Sm on
691.El
692.Pp
693Configuration options are defined as follows:
694.Bl -tag -width 10n
695.It Ar devpath
696Accepted device paths are:
697.Ar /dev/blockdev
698or
699.Ar /path/to/image
700or
701.Cm ram= Ns Ar size_in_MiB .
702.It Cm maxq
703Max number of queues.
704.It Cm qsz
705Max elements in each queue.
706.It Cm ioslots
707Max number of concurrent I/O requests.
708.It Cm sectsz
709Sector size (defaults to blockif sector size).
710.It Cm ser
711Serial number with maximum 20 characters.
712.It Cm eui64
713IEEE Extended Unique Identifier (8 byte value).
714.It Cm dsm
715DataSet Management support.
716Supported values are:
717.Cm auto , enable ,
718and
719.Cm disable .
720.El
721.Pp
722AHCI device backends:
723.Bl -bullet
724.It
725.Sm off
726.Op Oo Cm hd\&: | cd\&: Oc Ar path
727.Op Cm ,nmrr= Ar nmrr
728.Op Cm ,ser= Ar #
729.Op Cm ,rev= Ar #
730.Op Cm ,model= Ar #
731.Sm on
732.El
733.Pp
734Configuration options are defined as follows:
735.Bl -tag -width 10n
736.It Cm nmrr
737Nominal Media Rotation Rate, known as RPM.
738Value 1 will indicate device as Solid State Disk.
739Default value is 0, not report.
740.It Cm ser
741Serial Number with maximum 20 characters.
742.It Cm rev
743Revision Number with maximum 8 characters.
744.It Cm model
745Model Number with maximum 40 characters.
746.El
747.Pp
748HD Audio device backends:
749.Bl -bullet
750.It
751.Sm off
752.Op Cm play= Ar playback
753.Op Cm ,rec= Ar recording
754.Sm on
755.El
756.Pp
757Configuration options are defined as follows:
758.Bl -tag -width 10n
759.It Cm play
760Playback device, typically
761.Ar /dev/dsp0 .
762.It Cm rec
763Recording device, typically
764.Ar /dev/dsp0 .
765.El
766.It Fl U Ar uuid
767Set the universally unique identifier
768.Pq UUID
769in the guest's System Management BIOS System Information structure.
770By default a UUID is generated from the host's hostname and
771.Ar vmname .
772.It Fl u
773RTC keeps UTC time.
774.It Fl W
775Force virtio PCI device emulations to use MSI interrupts instead of MSI-X
776interrupts.
777.It Fl w
778Ignore accesses to unimplemented Model Specific Registers (MSRs).
779This is intended for debug purposes.
780.It Fl x
781The guest's local APIC is configured in x2APIC mode.
782.It Fl Y
783Disable MPtable generation.
784.It Ar vmname
785Alphanumeric name of the guest.
786This should be the same as that created by
787.Xr bhyveload 8 .
788.El
789.Sh CONFIGURATION VARIABLES
790.Nm
791uses an internal tree of configuration variables to describe global and
792per-device settings.
793When
794.Nm
795starts,
796it parses command line options (including config files) in the order given
797on the command line.
798Each command line option sets one or more configuration variables.
799For example,
800the
801.Fl s
802option creates a new tree node for a PCI device and sets one or more variables
803under that node including the device model and device model-specific variables.
804Variables may be set multiple times during this parsing stage with the final
805value overriding previous values.
806.Pp
807Once all of the command line options have been processed,
808the configuration values are frozen.
809.Nm
810then uses the value of configuration values to initialize device models
811and global settings.
812.Pp
813More details on configuration variables can be found in
814.Xr bhyve_config 5 .
815.Sh DEBUG SERVER
816The current debug server provides limited support for debuggers.
817.Ss Registers
818Each virtual CPU is exposed to the debugger as a thread.
819.Pp
820General purpose registers can be queried for each virtual CPU, but other
821registers such as floating-point and system registers cannot be queried.
822.Ss Memory
823Memory (including memory mapped I/O regions) can be read and written by the debugger.
824Memory operations use virtual addresses that are resolved to physical addresses
825via the current virtual CPU's active address translation.
826.Ss Control
827The running guest can be interrupted by the debugger at any time
828.Pq for example, by pressing Ctrl-C in the debugger .
829.Pp
830Single stepping is only supported on Intel CPUs supporting the MTRAP VM exit.
831.Pp
832Breakpoints are supported on Intel CPUs that support single stepping.
833Note that continuing from a breakpoint while interrupts are enabled in the
834guest may not work as expected due to timer interrupts firing while single
835stepping over the breakpoint.
836.Sh SIGNAL HANDLING
837.Nm
838deals with the following signals:
839.Pp
840.Bl -tag -width SIGTERM -compact
841.It SIGTERM
842Trigger ACPI poweroff for a VM
843.El
844.Sh EXIT STATUS
845Exit status indicates how the VM was terminated:
846.Pp
847.Bl -tag -width indent -compact
848.It 0
849rebooted
850.It 1
851powered off
852.It 2
853halted
854.It 3
855triple fault
856.It 4
857exited due to an error
858.El
859.Sh EXAMPLES
860If not using a boot ROM, the guest operating system must have been loaded with
861.Xr bhyveload 8
862or a similar boot loader before
863.Xr bhyve 4
864can be run.
865Otherwise, the boot loader is not needed.
866.Pp
867To run a virtual machine with 1GB of memory, two virtual CPUs, a virtio
868block device backed by the
869.Pa /my/image
870filesystem image, and a serial port for the console:
871.Bd -literal -offset indent
872bhyve -c 2 -s 0,hostbridge -s 1,lpc -s 2,virtio-blk,/my/image \\
873  -l com1,stdio -A -H -P -m 1G vm1
874.Ed
875.Pp
876Run a 24GB single-CPU virtual machine with three network ports, one of which
877has a MAC address specified:
878.Bd -literal -offset indent
879bhyve -s 0,hostbridge -s 1,lpc -s 2:0,virtio-net,tap0 \\
880  -s 2:1,virtio-net,tap1 \\
881  -s 2:2,virtio-net,tap2,mac=00:be:fa:76:45:00 \\
882  -s 3,virtio-blk,/my/image -l com1,stdio \\
883  -A -H -P -m 24G bigvm
884.Ed
885.Pp
886Run an 8GB quad-CPU virtual machine with 8 AHCI SATA disks, an AHCI ATAPI
887CD-ROM, a single virtio network port, an AMD hostbridge, and the console
888port connected to an
889.Xr nmdm 4
890null-modem device.
891.Bd -literal -offset indent
892bhyve -c 4 \\
893  -s 0,amd_hostbridge -s 1,lpc \\
894  -s 1:0,ahci,hd:/images/disk.1,hd:/images/disk.2,\\
895hd:/images/disk.3,hd:/images/disk.4,\\
896hd:/images/disk.5,hd:/images/disk.6,\\
897hd:/images/disk.7,hd:/images/disk.8,\\
898cd:/images/install.iso \\
899  -s 3,virtio-net,tap0 \\
900  -l com1,/dev/nmdm0A \\
901  -A -H -P -m 8G
902.Ed
903.Pp
904Run a UEFI virtual machine with a display resolution of 800 by 600 pixels
905that can be accessed via VNC at: 0.0.0.0:5900.
906.Bd -literal -offset indent
907bhyve -c 2 -m 4G -w -H \\
908  -s 0,hostbridge \\
909  -s 3,ahci-cd,/path/to/uefi-OS-install.iso \\
910  -s 4,ahci-hd,disk.img \\
911  -s 5,virtio-net,tap0 \\
912  -s 29,fbuf,tcp=0.0.0.0:5900,w=800,h=600,wait \\
913  -s 30,xhci,tablet \\
914  -s 31,lpc -l com1,stdio \\
915  -l bootrom,/usr/local/share/uefi-firmware/BHYVE_UEFI.fd \\
916   uefivm
917.Ed
918.Pp
919Run a UEFI virtual machine with a VNC display that is bound to all IPv6
920addresses on port 5900.
921.Bd -literal -offset indent
922bhyve -c 2 -m 4G -w -H \\
923  -s 0,hostbridge \\
924  -s 4,ahci-hd,disk.img \\
925  -s 5,virtio-net,tap0 \\
926  -s 29,fbuf,tcp=[::]:5900,w=800,h=600 \\
927  -s 30,xhci,tablet \\
928  -s 31,lpc -l com1,stdio \\
929  -l bootrom,/usr/local/share/uefi-firmware/BHYVE_UEFI.fd \\
930   uefivm
931.Ed
932.Pp
933Run a UEFI virtual machine with a VARS file to save EFI variables.
934Note that
935.Nm
936will write guest modifications to the given VARS file.
937Be sure to create a per-guest copy of the template VARS file from
938.Pa /usr .
939.Bd -literal -offset indent
940bhyve -c 2 -m 4g -w -H \\
941  -s 0,hostbridge \\
942  -s 31,lpc -p com1,stdio \\
943  -l bootrom,/usr/local/share/uefi-firmware/BHYVE_UEFI_CODE.fd,BHYVE_UEFI_VARS.fd
944   uefivm
945.Ed
946.Sh SEE ALSO
947.Xr bhyve 4 ,
948.Xr netgraph 4 ,
949.Xr ng_socket 4 ,
950.Xr nmdm 4 ,
951.Xr vmm 4 ,
952.Xr bhyve_config 5 ,
953.Xr ethers 5 ,
954.Xr bhyvectl 8 ,
955.Xr bhyveload 8
956.Pp
957.Rs
958.%A Intel
959.%B 64 and IA-32 Architectures Software Developer’s Manual
960.%V Volume 3
961.Re
962.Sh HISTORY
963.Nm
964first appeared in
965.Fx 10.0 .
966.Sh AUTHORS
967.An Neel Natu Aq Mt neel@freebsd.org
968.An Peter Grehan Aq Mt grehan@freebsd.org
969