This may be stating the obvious but I think it’s worth repeating. Before building a Virtual SAN enabled cluster make sure:

  • The server hardware is updated to the latest and greatest system ROM / BIOS / firmware
  • The IO Controller is running the latest firmware
  • The SSD are running the latest firmware
  • The HDD are running the latest firmware

These firmware updates often resolve some important hardware issues.

Next, make sure you follow the Performance Best Practices for VMware vSphere® 5.5

  • Specifically, make sure Power Management BIOS Settings are disabled in the server BIOS (see page 17)

Once ESXi is installed on the host

  • Make sure the IO Controller is loading the correct version of the device driver.  You can look this up on the Virtual SAN HCL

I work with a lot of customers who are evaluating or implementing Virtual SAN and following these simple, obvious, but important best practices have led to better performance and a better overall experience with Virtual SAN.