vm-bhyve No disk(s) present to configure

[John Doherty]

Hi, I am trying to get started with vm-bhyve and getting a little stuck. 
I am sure there are things I don't understand here so I hope you will 
bear with me.

I am using a machine with an AMD FX-8370E eight-core CPU, running 
12.2-RELEASE-p4. The machine boots from a ~60GB SATA SSD which is 
configured as the zroot zpool.

I have run a few bhyve vms on this machine before, including a couple of 
linux variants, by just using the bhyve command directly and they worked 
fine. In those cases, I just used files created with truncate(1) for vm 
disks but I would like to use zvols. vm-bhyve looks pretty nice to me 
and I think I'd like using it also.

I have this in /boot/loader.conf:

	vmm_load="YES"
	nmdm_load="YES"
	if_tap_load="YES"
	if_bridge_load="YES"

and this in /etc/rc.conf:

	vm_enable="YES"
	vm_dir="zfs:zroot/vmm"
	vm_list=""
	vm_delay="5"

And so I thus have this:

	[root at sand] # zfs list -r zroot/vmm
	NAME        USED  AVAIL  REFER  MOUNTPOINT
	zroot/vmm  1.43G  36.8G  1.43G  /vmm

and this:

	[root at sand] # vm datastore list
	NAME            TYPE        PATH      ZFS DATASET
	default         zfs         /vmm      zroot/vmm

I have populated /vmm/.templates with the files from 
/usr/local/share/examples/vm-bhyve but made some changes to them. For 
example, the freebsd-zvol.conf template now looks like this:

	loader="bhyveload"
	cpu=1
	memory=4096M
	network0_type="virtio-net"
	network0_switch="public"
	disk0_dev="sparse-zvol"
	disk0_name="disk0"

I've also populated /vmm/.iso with some ISO images including 
FreeBSD-12.2-RELEASE-amd64-disc1.iso.

So with that, I can for example do this:

	[root at sand] # vm create -t freebsd-zvol fbsd1
	[root at sand] # vm list
	NAME   DATASTORE  LOADER     CPU  MEMORY  VNC  AUTOSTART  STATE
	fbsd1  default    bhyveload  1    4096M   -    No         Stopped

and zfs things then look like this:

	[root at sand] # zfs list -r zroot/vmm
	NAME                    USED  AVAIL  REFER  MOUNTPOINT
	zroot/vmm              1.43G  36.8G  1.43G  /vmm
	zroot/vmm/fbsd1         164K  36.8G   108K  /vmm/fbsd1
	zroot/vmm/fbsd1/disk0    56K  36.8G    56K  -

So that all seems pretty good so far. Then I do this:

	vm install -f fbsd1 FreeBSD-12.2-RELEASE-amd64-disc1.iso

The vm boots and I'm asked to choose a console type, I take the default 
vt100, and boom -- I get the familiar FreeBSD Installer screen. I 
proceed through that and try to do a Guided Root-on-ZFS installation, 
but when I choose Pool Type/Disks, I'm told "No disk(s) present to 
configure."

So. Pretty clearly doing something wrong here but I'm not sure what. 
Happy to provide any further info that I might have neglected above. Any 
advice that points me in the right direction much appreciated. Thanks.