I’m having some challenges in deciding how to implement my storage. Of course, I could just go to the VMware Whitelist and pick the latest and greatest RAID controller. The same card would cost more than the rest of the system all together and that’s simply not an option. The goal is to get the minimal card to solve my current need and therefor I need to get a good overview of the reasonable solutions.

1. No RAID what-so-ever
   This method would cost nothing and be quite simple, hardware wise, to implement – Just plug in the drives to the Intel onboard SATA controller. I could create redundancy with some software routines and set up virtual disk images in each datastore. However, if any disk would go down I would have to shut down the entire system and fix the problem.
2. Pass-through of onboard controller
   This is an interesting alternative. I could pass the entire onboard SATA controller to a single virtual machine. After that I could do software RAID in Linux on some of the drives. However, it’s not possible to just pass a subset of the SATA ports to a VM. It’s all or none ports. Therefor I won’t have any place to put the VM itself. Catch 22…
3. Hardware RAID
   Intel’s onboard SATA controller is only capable of software RAID which is not supported by ESXi so this alternative needs a competent controller. There are also some options within this alternative.
   • RAID of the entire environment
     The ESXi would only see the storage in whatever way I set up the RAID. This way everything regarding the virtual machines that reside on a redundant drive set would be covered. This is somewhat tempting but I’m not really sure on how to supervise the RAID sets.
   • Pass on the controller to a VM
     Once again, I could pass the entire controller to a VM and then set up RAID at a software level. The positive thing with passing on a separate controller is that I still have the onboard controller to store non important stuff as ISO images and test VMs. Another appealing thing is that the content of the drives would be only the relevant stuff. The OS resides on the datastore connected to the onboard storage and only the important information would be RAIDed.

I have pretty much decided on going with the last option. Perhaps this is one way to illustrate how i intend to solve it:

• USB Controller
  • USB Drive with the ESXi host
• Onboard SATA controller
  • 1TB drive with VMs and ISOs
• PCI-Express SATA controller, passed on to a VM
  • 4x1TB drives setup with software RAID