1. The virtual appliance
With the Checkmk virt1 virtual appliance you can run Checkmk as a guest on an existing virtualisation platform (hypervisor) such as VMware ESXi. VirtualBox is also supported and is particularly suitable for testing.
The operating system and a web interface for administration are already pre-installed in the appliance. The appliance is set up via a dialog, configured via the web interface and is ready for immediate use after a few simple steps — you therefore do not need any prior Linux knowledge.
2. Download the appliance
If you have a valid subscription with the Checkmk virt1 option, you can find the appliance software for the Standard Edition and Managed Services Edition in the customer portal.
As an alternative, you can download the virtual appliance for the Free Edition from the download page.
The following file types are available for virtual appliance download:
OVA file: The virtual appliance Checkmk virt1 to import into the hypervisor. OVA stands for Open Virtualization Archive and is the archive format of the Open Virtualization Format (OVF). The OVA file can be found in the download area at the product Checkmk appliance.
You will need this file for the installation.
CFW file: The appliance firmware. Just like the OVA file, a CFW file is provided in the download area for each appliance version. You can use this file to update an already-installed appliance during operation. The firmware update is done with the appliance web interface.
You do not need the CFW file for the initial installation, as the OVA file already contains the firmware.
CMA file: The Checkmk software for installation in the appliance. Starting with appliance version 1.4.14, no Checkmk software is pre-installed in the appliance. You also carry out the installation of the Checkmk software with the appliance web interface. The CMA file is available in the download area after selecting the Checkmk edition, version and platform appliance.
You will only need the CMA file after the installation is complete — when you configure the appliance.
Download the OVA file for the installation of the virtual appliance.
3. Installation under VirtualBox
3.1. Prerequisites
For the following steps, you need an operational VirtualBox installation in addition to the OVA file. It does not matter on which system VirtualBox is running.
3.2. Import the appliance
Start the import of the OVA file via File > Import Appliance and select the OVA file. You will then see all virtual machine settings — and can leave these as they are. Of course you can change the values at this point or later, for example, to give the machine additional resources.
Important: Under the appliance settings, it is essential to select the Generate new MAC addresses for all network adapters under MAC Address Policy. Otherwise problems will occur if multiple appliances with the same MAC address run on the network.

You can now import the appliance.
After the import, you must perform another step: Call up the virtual machine’s network configuration. The mode is set to Bridged Adapter here — the virtual network adapter is connected to an adapter on your host — and these of course vary. In case of doubt simply leave the configuration without any changes with OK — VirtualBox then automatically selects your default adapter for the missing adapter.

This completes the VirtualBox-specific actions. Your appliance is now ready to start and you can begin with the basic configuration.
4. Installation under ESXi
4.1. Prerequisites
You need the OVA file of the appliance. Also, you already have an ESXi server running in the network and have set up a data store in it for the virtual machine configurations.
4.2. Import the appliance
The import of the appliance runs largely automatically — only afterwards you should take another look at the network configuration.
In the ESXi main navigation, select Virtual Machines.
Start the import wizard via Create/Register VM.
Select the import via OVA/OVF.
Add the OVA file.
Follow the wizard without doing any further changes.
The new machine will then be deployed, which may take a few minutes.

Important: The Checkmk virt1 comes with an E1000 type network interface — an emulation of the 1GB Intel 82545EM Gigabit Ethernet NIC network adapter-- for which the drivers are usually already available. On an ESXi server, for better performance you should exchange the card for a card of the VMXNET 3 type, i.e. for a completely-virtualized 10 GB interface.
To do this, install VMWare tools and change the setting under virt1 > Edit > Network Adapter 1 > Adapter Type:

You have now completed the VMWare ESXi-specific steps. Your appliance is now ready to start and you can begin with the basic configuration.