I would like to use PRTG. However, we can only install it on a virtual machine. Can I use Linux OS in the virtual machine to run the PRTG?

This article applies as of PRTG 25

PRTG on Linux

It is currently not possible to install a PRTG core server on Linux/Unix systems. In order to run a PRTG core server you need a Windows machine. You can find our requirements here.

Additionally, we recommend that you run PRTG on real hardware (especially when using more than 5,000 sensors). If you must run PRTG on a virtual machine, please have a look here for configuration and fine-tuning recommendations.

Alternatives

If you only have Linux systems, you can use PRTG Hosted Monitor, our hosted PRTG instance, in conjunction with multi-platform probes. 

The multi-platform probe is a remote probe that functions on various non-Windows systems. For more information, see the Multi-Platform Probe for PRTG manual. 

For more information on how to use the multi-platform probe with PRTG Hosted Monitor, see the Knowledge Base: How do I set up a multi-platform probe with my PRTG Hosted Monitor instance?