Product : Dell EMC, VxRail [HCI]/4.7.212, x86
Feature : Flash Capacity, Flash, Storage Support
Content Owner:  Herman Rutten
Summary
Hybrid: 4 Flash devices per node
All-Flash: 2-24 Flash devices per node
Details
Each VxRail node always requires 1 high-performance SSD for write caching.

In Hybrid VxRail configurations the high-performance SSD in a disk group is also used for read caching. Per disk group 3-5 HDDs can be used as persistent storage (capacity drives).

In All-Flash VxRail configurations the high-performance SSD in a disk group is only used for write caching. Per node 1-5 SSDs can be used for read caching and persistent storage (capacity drives).