BHYVELOAD(8)            FreeBSD System Manager's Manual           BHYVELOAD(8)

NAME

     bhyveload - load a FreeBSD guest inside a bhyve virtual machine

SYNOPSIS

     bhyveload [-C] [-S] [-c cons-dev] [-d disk-path] [-e name=value]
               [-h host-path] [-l os-loader] [-m memsize[K|k|M|m|G|g|T|t]]
               vmname

DESCRIPTION

     bhyveload is used to load a FreeBSD guest inside a bhyve(4) virtual
     machine.

     bhyveload is based on loader(8) and will present an interface identical
     to the FreeBSD loader on the user's terminal.  This behavior can be
     changed by specifying a different OS loader.

     The virtual machine is identified as vmname and will be created if it
     does not already exist.

OPTIONS

     The following options are available:

     -c cons-dev
             cons-dev is a tty(4) device to use for bhyveload terminal I/O.

             The text string "stdio" is also accepted and selects the use of
             unbuffered standard I/O. This is the default value.

     -d disk-path
             The disk-path is the pathname of the guest's boot disk image.

     -e name=value
             Set the FreeBSD loader environment variable name to value.

             The option may be used more than once to set more than one
             environment variable.

     -h host-path
             The host-path is the directory at the top of the guest's boot
             filesystem.

     -l os-loader
             Specify a different OS loader.  By default bhyveload will use
             /boot/userboot.so, which presents a standard FreeBSD loader.

     -m memsize[K|k|M|m|G|g|T|t]
             memsize is the amount of memory allocated to the guest.

             The memsize argument may be suffixed with one of K, M, G or T
             (either upper or lower case) to indicate a multiple of Kilobytes,
             Megabytes, Gigabytes or Terabytes respectively.

             memsize defaults to 256M.

     -C      Include guest memory in the core file when bhyveload dumps core.
             This is intended for debugging an OS loader as it allows
             inspection of the guest memory.

     -S      Wire guest memory.

EXAMPLES

     To create a virtual machine named freebsd-vm that boots off the ISO image
     /freebsd/release.iso and has 1GB memory allocated to it:

           bhyveload -m 1G -d /freebsd/release.iso freebsd-vm

     To create a virtual machine named test-vm with 256MB of memory allocated,
     the guest root filesystem under the host directory /user/images/test and
     terminal I/O sent to the nmdm(4) device /dev/nmdm1B

           bhyveload -m 256MB -h /usr/images/test -c /dev/nmdm1B test-vm

SEE ALSO

     bhyve(4), nmdm(4), vmm(4), bhyve(8), loader(8)

HISTORY

     bhyveload first appeared in FreeBSD 10.0, and was developed at NetApp
     Inc.

AUTHORS

     bhyveload was developed by Neel Natu <neel@FreeBSD.org> at NetApp Inc
     with a lot of help from Doug Rabson <dfr@FreeBSD.org>.

BUGS

     bhyveload can only load FreeBSD as a guest.

SECURITY CONSIDERATIONS

     Note that in some configurations, bhyveload will execute guest loader
     scripts in the context of the host machine.  Note, however, that
     bhyveload will enter a capsicum(4) sandbox before it loads the os-loader
     or executes any loader scripts.  On the host filesystem, the sandbox will
     only have access to the path specified by the -h flag, the contents of
     the /boot directory if -l was not specified, and the chosen console
     device.

     Note that the guest loader scripts are already subject to some
     limitations that are not relaxed simply because we are running in
     userland.  For instance, any I/O on the loader's "host" device that can
     be done in loader scripts is limited to the interface that bhyveload
     provides, which itself will restrict paths that can be touched to those
     within a specified -h directory, if any.  Access to files within /boot
     inside the sandbox would require arbitrary code execution in userboot,
     and userboot is usually provided by the host machine rather than anything
     that is a part of the guest image.  All access to the -h directory as
     well as /boot is strictly read-only in the sandbox.

FreeBSD 15.1-STABLE-HBSD       January 12, 2024                   BHYVELOAD(8)