haggis663/bmt

BMT - Bhyve Management Tool

This is a super lightweight yet very functional tool to manage Bhyve VMs on FreeBSD. It needs:

• /bin/sh
• A ZFS volume to place VMs into (UFS is not supported)
• GNU screen (pkg install screen)
• Grub2 Bhyve loader (pkg install grub2-bhyve)
• BHyve UEFI Firmware, if you'll be running Windows VMs (pkg install -y bhyve-firmware)

It supports most UNIX OSes and Window, handles auto-booting VMs at system start and shutting them down at system shutdown/reboot.

Initial Setup

ZVol Location

By default BMT will create a ZFS volume zroot/vms to house the VM configs and virtual disks, and mount the base in /usr/local/vms.

If you wish to have this somewhere else (ie; if you wish to place it on a different zroot) create a file called /usr/local/etc/bmt.conf:

# Base ZFS Root
BASE_ZPATH="zssd/vms" 

Where zssd is your preferred base ZFS.

Init

The first time setting up BMT on a system (assumes bmt is installed into /usr/local/bmt/):

ln -s /usr/local/bmt/bmt.rc.sh /usr/local/etc/rc.d/bmt &&
sysrc bmt_enable="YES" &&
bmt rcstart &&
bmt setup

It is best to reboot after this just to be sure everything is applied.

Usage

You can run just bmt to get a list of options. This section needs to be expanded more but the following should get you started:

List All VMs

bmt list will show all VMs, their states, used memory, CPU and if they're set to come up on system boot.

Network Map

The bmt netmap command will attempt to map out VM's TAP devices an label them in an easy to understand way against each bridge.

You can specify user-friendly labels for the bridges by adding the following format lines to /usr/local/etc/bmt.conf:

BRIDGE_bridge0_NAME="Private LAN"
BRIDGE_bridge1_NAME="Public WAN"

New VM

To create a new VM with a 16 GiB virtual disk:

bmt create newvmname -V 16G

Edit VM

bmt edit <vname> launches opens the appropriate vm.conf file in your preferred editor.

Start/Stop

To stop a VM:

bmt stop vmname

To start a VM:

bmt start vmname

(Where "vmname" is the name you gave it).

Attach To Console

To attach to the text console:

mt attach vmname

Networking

By default with AUTO_NETWORKING="YES" set for a VM, a TAP device will automatically be created and assigned to bridge0 (for the example below).

NOTE: It will not automatically create bridge0, you still need to set that up in /etc/rc.conf and ifconfig

This auto-provisioning can be overridden via these config blocks:

# -- Networking
#    Up to 12 nics are possible following the same naming convention )
#
AUTO_NETWORKING="NO" 
VM_N1_BRIDGE_NUM="0" 
VM_N1_TAP_NUM="21" 

VM_N2_BRIDGE_NUM="" 
VM_N2_TAP_NUM="" 

NOTE: If you have PF enabled make sure to 'skip' any VM taps and bridges /etc/pf.conf:

set skip on bridge0
set skip on tap21

Otherwise nothing will work. Obviously you can apply more granular control over this but this is a common issue when VM networking doesn't work.