NC

I was trying to setup a quick (…foreshadowing) VM to run a VPN on a host I use for a few VMs with KVM. But getting it setup was surprisingly painful until I tried the “nano” install image.

As the host is headless, I wanted a disk image I could import on the host with Opnsense already installed to avoid trying to redirect VNC over the network, or something similarly daft. A serial terminal was ideal (and how virt-install and the rest of libvirt works nicest). Alas, I couldn’t get a serial terminal configured correctly with the dvd image (it’d output boot logs, but when I got to the stage of interacting with the console it would stop outputting anything), the docs only mention using the Web UI which I couldn’t do at that stage of the install, and then the USB serial image just wouldn’t boot.

But the nano image provided the eventual solution: it’s designed to be written to a disk and then just booted where it expands to fill the new volume and serial is already configured. Perfect, but it wasn’t clear how to do it. So:

1. Fetch and extract the image from the download page:

wget https://mirror.ams1.nl.leaseweb.net/opnsense/releases/24.1/OPNsense-24.1-nano-amd64.img.bz2
bunzip2 OPNsense-24.1-nano-amd64.img.bz2

1. Convert to a qcow2 disk image: qemu-img convert -f raw -O qcow2 OPNsense-24.1-nano-amd64.img OPNsense-24.1-nano-amd64.qcow2
2. Resize to give us more space for logs, etc: qemu-img resize OPNsense-24.1-nano-amd64.qcow2 +8G
3. Rename/put the disk somewhere helpful: cp OPNsense-24.1-nano-amd64.qcow2 opnsense.qcow2
4. Use virt-install to import into a new VM:

virt-install --connect qemu:///system \
  --name opnsense \
  --os-variant freebsd12.2 \
  --memory 4096 \
  --disk opnsense.qcow2 \
  --network default \
  --graphics none \
  --console pty,target_type=serial \
  --import

Hopefully this saves someone some future bother!