This article by Josh Paetzel informs users on implementing FreeNAS in a virtualized environment.
FreeNAS is the world’s most popular open source storage OS, and one of the more popular questions I get asked is, “How do I run FreeNAS as a VM?” Due to the number of caveats required to answer that question, I would typically short-circuit the conversation by recommending against it, or only recommend it for test environments since the prerequisite knowledge required to “do it right” can’t be passed on quickly. Somehow over time, this message morphed into a general consensus that “you cannot (or shouldn’t) virtualize FreeNAS at all under any circumstances”, which wasn’t my intention. So, I’m here to set the record straight once and for all: You absolutely can virtualize FreeNAS.
Whether you are test driving the functionality of FreeNAS, testing an upgrade for compatibility in your environment, or you want to insulate your FreeNAS system from hardware faults, virtualization can provide many well understood benefits. That said, while FreeNAS can and will run as a virtual machine, it’s definitely not ideal for every use case. If you do choose to run FreeNAS under virtualization, there are some caveats and precautions that must be considered and implemented. In this post I’ll describe what they are so that you can make well-informed choices.
Before we get started though, I should probably start with a disclaimer…
If best practices and recommendations for running FreeNAS under virtualization are followed, FreeNAS and virtualization can be smooth sailing. However, failure to adhere to the recommendations and best practices below can result in catastrophic loss of your ZFS pool (and/or data) without warning. Please read through them and take heed.