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+---
+title: "Installing Opnsense with virt-install on KVM"
+tags: opnsense kvm
+---
+
+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][2] already installed to avoid trying to redirect VNC over the 
+network, or something similarly daft. A serial terminal was ideal (and how 
+[`virt-install`][3] 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)][5], [the docs only mention using the Web UI][4] 
+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][1]:
+
+```
+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
+```
+
+2. 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`
+3. Resize to give us more space for logs, etc: `qemu-img resize OPNsense-24.1-nano-amd64.qcow2 +8G`
+4. Rename/put the disk somewhere helpful: `cp OPNsense-24.1-nano-amd64.qcow2 opnsense.qcow2`
+5. 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!
+
+[1]: https://opnsense.org/download/
+[2]: https://opnsense.org
+[3]: https://manpages.debian.org/stable/virtinst/virt-install.1.en.html
+[4]: https://docs.opnsense.org/manual/how-tos/serial_access.html
+[5]: https://forums.freebsd.org/threads/installing-freebsd-over-serial-console.62005/#post-357713