How to install FreeBSD VM on FreeBSD using bhyve and ZFS.

`1. Preparing the Host`

First, load the bhyve kernel module:

# kldload vmm

Then, create a tap interface for the network device in the virtual machine

to attach to. In order for the network device to participate in the network,

also create a bridge interface containing the tap interface and the physical

interface as members. In this example, the physical interface is em0:

# ifconfig tap0 create

# sysctl net.link.tap.up_on_open=1

net.link.tap.up_on_open: 0 -> 1

# ifconfig bridge0 create

# ifconfig bridge0 addm em0 addm tap0

# ifconfig bridge0 up

If ZFS is available on the host machine, using ZFS volumes instead of disk

image file can provide significant performance benefits for the guest VMs.

A ZFS volume can be created by:

# zfs create -V16G -o volmode=dev zroot/freebsddisk0

Download an installation image of FreeBSD to install:

https://download.freebsd.org/ftp/releases/ISO-IMAGES/13.0/

or

https://wiki.freebsd.org/Torrents to iso via qiBttorrent.

FreeBSD comes with an example script for running a virtual machine in bhyve.

The script will start the virtual machine and run it in a loop, so it will

automatically restart if it crashes. The script takes a number of options to

control the configuration of the machine: -c controls the number of virtual

CPUs, -m limits the amount of memory available to the guest, -t defines which

tap device to use, -d indicates which disk image to use, -i tells bhyve to

boot from the CD image instead of the disk, and -I defines which CD image

to use.The last parameter is the name of the virtual machine, used to track

the running machines. This example starts the virtual machine in installation

mode:

# sh /usr/share/examples/bhyve/vmrun.sh \

-c 1 -m 1024M -t tap0 -d /dev/zvol/zroot/freebsddisk0 -i \

-I /path/to/FreeBSD.iso freebsdguest

The virtual machine will boot and start the installer.After installing a

system in the virtual machine, when the system asks about dropping in to a

shell at the end of the installation, choose Yes.

Reboot the virtual machine. While rebooting the virtual machine causes

bhyve to exit, the vmrun.sh script runs bhyve in a loop and will automatically

restart it. When this happens, choose the reboot option from the boot loader

menu in order to escape the loop. Now the guest can be started from the virtual disk:

# sh /usr/share/examples/bhyve/vmrun.sh -c 1 -m 1024M \

-t tap0 -d /dev/zvol/zroot/freebsddisk0 freebsdguest

In order to configure the system to start bhyve guests at boot time, the

following configurations must be made in the specified files:

3.1. /etc/sysctl.conf

net.link.tap.up_on_open=1

3.2. /etc/rc.conf

cloned_interfaces="bridge0 tap0"

ifconfig_bridge0="addm em0 addm tap0"

kld_list="vmm"