Virtual & Cloud based Installation


Installing OPNsense on a virtual machine can be done by using the cdrom iso image. Full instructions are available in chapter Initial Installation & Configuration .

General tips

For optimum performance and compatibility, these guides are given:

  • Minimum required RAM is 1 GB
  • Minimum recommended virtual disk size of 8GB
  • Disable all off-loading settings in Interfaces->Settings

VMware ESXi

VMware offers full instructions for installing FreeBSD, these can be found here.

To install the VMware tools just goto System->Firmware->Plugins and install os-vmware by clicking on the + sign next to it.



While other network setups may work fine, the e1000 driver seems to work best, certainly when utilizing the traffic shaper.


To install the Xen tools just goto System->Firmware->Plugins and install os-xen by clicking on the + sign next to it.



HyperV is supported out of the box, no additional drivers or tools are needed.


FreeBSD version 10.2 was released with a HyperV bug, therefore OPNsense version 16.1 of the installation media will not function correctly. The bug will be resolved in later installation media. The solution for new installations are (till new media is released) to install the 15.7 version ( )and upgrade to the latest using the GUI or opnsense-update cli tool.


OPNsense can be installed on all virtual machines that support FreeBSD (such as KVM, Bhyve, VirtualBox).


For hosted installations where you can’t install using the cdrom iso an alternative approach is available in the form of opnsense-bootstrap.


opnsense-bootstrap(8) is a tool that can completely reinstall a running system in place for a thorough factory reset or to restore consistency of all the OPNsense files. It can also wipe the configuration directory, but won’t do that by default.

It will automatically pick up the latest available version and build a chain of trust by using current package fingerprints -> CA root certificates -> HTTPS -> OPNsense package fingerprints.

What it will also do is turn a supported stock FreeBSD 10 release into an OPNsense installation, given that UFS was used to install the root file system.

opnsense bootstrap is available for our github source repository

Amazon AWS EC2 Cloud


Installing OPNsense into the Amazon cloud can be a dounting task as no console is offered. As part of Deciso’s support packages (see OPNsense commercial Support), deciso offer free access to its OPNsense Amazon Machine Image (AMI).

See also our how-to for Installing OPNsense AWS image.

Common Issues

Some common issues have been reported for different virtual environments. You can find known solutions to these problems below.

If you problem is not listed always try the General tips as mentioned in the article first.

File copy failed during installation

This issue is most likely caused by low memory setting. Make sure your virtual OPNsense installation has a minimum of 1GB of RAM.

Disk Errors on VMware

This issue can be caused by a defective drive. Changing drive mode to IDE has been reported to help for certain ESXi versions.

Installation failure on KVM

If you are using virtio for the root disk then try switching to sata mode.

NAT issues on XenServer

This issue has been reported to be solved by disabling cheksum offloading on both OPNsense domU and Vifs.

Traffic Shaper does not work on VMware

If you are using vmxnet3 drivers try to switch to E1000.