Installation Procedure

Download the OPNsense ISO from your Proxmox VE

1. Under Datacenter, select the node where you plan to download the ISO, then click on a volume (by default, ’local’).
2. Navigate to ISO Images, click Download from URL, and check the Advanced box.
3. In the URL box, paste the download link for the dvd installer found on the official download page (or in a mirror).
4. Name the file or click the Query URL button.
5. Click the Hash Algorithm drop-down list and select SHA-256.
6. Paste the checksum provided on the download page in the Checksum box, and ensure that the decompression algorithm is BZIP2.
7. Proceed to download.

Create a virtual machine

1. Once the download has completed, click the Create VM button in the top-right-hand corner, and check the Advanced box.
2. Give the VM a sensible name.
3. Check Start at boot.
4. Under OS, select the ISO image starting with OPNsense, and select Other in the OS type drop-down list.
5. Under System > Firmware, select OVMF as a BIOS type, select the local-lvm EFI storage, and uncheck Pre-Enroll keys.
6. Under Disks, add your options. The only one I set is 16GiB of disk space.
7. Under CPU, add sensible options for your use case. I set mine to 1 socket, 2 cores.
8. Under Memory, add relevant options. In my case, 4096MB.
9. Given the role of OPNsense, I uncheck the Firewall box under Network. One should also set the NIC model to VirtIO for maximum performance.

Installation

1. Login as installer with password opnsense. On the first installer page, set your keyboard layout.
2. On the next page, select your filesystem type, for example ZFS. Proceed through the next steps until you confirm your choices (Last Chance! page).
3. The installation should complete without issues.
4. You may set the root password now, or ignore until you open the web interface.
5. When prompted to, select Reboot Now.
6. Once your VM has restarted, log in as root and type 12 to update the system. Say yes, review the changes and proceed.