Comprehensive and Detailed Explanation From Exact Extract:
To meet the requirement for at least two host failures tolerance while also maximizing usable disk space in a vSAN cluster, the recommended configuration is to use RAID-6 (Erasure Coding) with a "2 failures" policy. The necessary steps as described in VMware documentation are:
Create a new VM Storage Policy in the vSphere Client (D): Administrators should create a new policy rather than modify the default, to apply specific rules for select VMs.
Set Failures to Tolerate to "2 failures - RAID-6 (Erasure Coding)" in the policy configuration (C): This setting ensures that data can survive up to two host failures and provides higher usable capacity than RAID-1 mirroring.
Apply the storage policy to the target VMs (B): The new policy must be applied to the required virtual machines to ensure they benefit from the specified level of protection.
Using RAID-6 (Erasure Coding) is preferred for capacity efficiency, especially when compared to RAID-1, and aligns with the financial consideration of maximizing usable disk space. Thin provisioning is not directly related to fault tolerance or disk space efficiency in the context of failures to tolerate, and modifying the default policy is not best practice for granular requirements.