VMware Virtual SAN Cookbook

Selecting a solid-state drive (SSD) for the cache tier

In combination with the storage controller, the SSD for the cache tier is the most important choice you can make in terms of the long-term reliability and performance of your VSAN deployment. The cache-tier SSD is used for caching reads and writes in VSAN hybrid configurations, and for caching writes only in all-flash configurations. SSDs are graded in many ways, and these grades for performance, write resiliency, and fabrication technology will all affect your selection. The VSAN Compatibility Guide gives you an overview of all of these factors to help you make the best choice.

Note

For the SSD:

• The write-performance class is on a scale of A-F, with the F class being the fastest (class A is ...