bd

bd

bd (bhyve daemon) is a bhyve virtual machine manager for FreeBSD. It is similar to the vm-bhyve manager, but purposely seeks to implement less functionality.

The main goal of bd is to transparently expose bhyve's CLI configuration levers while adding the minimum amount of functionality required to operate bhyve processes.

Features

• Manages the full life cycle of a virtual machine - including creating, starting, stopping, restarting, and auto-starting virtual machines
• Automates the creation of virtual machine dependencies like tap devices and network configuration
• Configures virtual machines through a simple INI file which supports templating and directly exposes bhyve process arguments
• Multi-viewer serial console support via an unprivileged background process. Also supports logging serial console output to help debug VM kernel panics

Requirements

• FreeBSD
• zfs

Installation

# Note: All commands below should be run as the root user.

# Enable the vmm kernel module and load it:
sysrc kld_list+="vmm"
kldload vmm

# Install required dependencies:
pkg install bhyve-firmware go

# Compile and install bd:
su -m nobody -c 'cd $(mktemp -d) && export HOME="$(realpath .)" && go install codeberg.org/stephen-fox/bd@latest && realpath' | read tmp && cp -v "${tmp}/go/bin/bd" /usr/local/bin/bd

# Create the required directories and bd configuration file:
bd install

# Optional: Edit the bd configuration file:
# vim /usr/local/etc/bd/bd.conf

# Create VM storage and boot media zfs datasets (these can be customized):
zfs create zroot/vms
zfs create zroot/os-images

Quick start

After installing bd, we can create a virtual machine like this:

# Note: All commands below should be run as the root user.

su -m nobody -c 'fetch -o - https://download.freebsd.org/releases/amd64/amd64/ISO-IMAGES/15.1/FreeBSD-15.1-RELEASE-amd64-disc1.iso' | cat > /zroot/os-images/FreeBSD-15.1-RELEASE-amd64-disc1.iso

bd new fbsd-example

# Edit the configuration file and change the "InsertDisc" parameter's
# value to be: FreeBSD-15.1-RELEASE-amd64-disc1.iso
vim /usr/local/etc/bd/vm-configs/fbsd-example/vm.conf

bd start fbsd-example

bd console fbsd-example

Documentation

• Installation (see above)
• Commands
• Configuration

Project status

I have been using bd for nearly four years to manage virtual machines in jails. However, FreeBSD 15 seemingly broke support for running bhyve in a jail. I was already reconsidering my approach to using jails and, with the most recent breakage, decided to redesign bd to be more like vm-bhyve in September 2026. A lot changed in that code base, so I would say we are firmly in the "experimental" phase again.

For more details on why I made this change, refer to the commit message of e12c400.