Some very interesting links for your question:
- VMware Knowledge Base
- Adding RDMs to VMware SQL Cluster
VMworld-2019_BCA2861BU.pdf 1.9 MB
It's not mandatory, just recommended based on database total I/OPS. Whenever you have very high rate of read or write operations inside the SQL server guest OS (because of too much requests for database access) it can be a great action to assign a LUN from the stoage to the VM directly, so only that VM (SQL server) does R/W operations on that volume, especially when you replace it by disks with better IOPS.
However there are many best practice documents for SQL server virtualization, like those other Experts attached in this topic. I strongly recommend to read them too.Please mark my comment as the Correct Answer if this solution resolved your problem1 person found this helpful
Sorry amin, but in the kb 2147661 it seems to be mandatory... look at the table in the middle of the page...
What I have understood is that for cluster aross box RDM is still mandatory.