To deploy a new two-node vSAN cluster with a shared witness, the administrator must meet several requirements, one of which is that the ESXi hosts must have a minimum of 64 GBs of memory. This is because each host must have enough memory to run the VMs and also to support the vSAN metadata overhead. The other options are not requirements for a two-node vSAN cluster with a shared witness. The ESXi hosts do not need SSDs or NVMe for Virtual Flash File System, as they can use any supported storage devices for vSAN. The ESXi host’s controller cache and advanced features do not need to be disabled, as they can be used to improve performance and reliability. The ESXi host’s drives do not need to be configured in RAID 1, as vSAN uses its own software-defined RAID mechanism to provide Failures to Tolerate. References: Shared Witness for 2-Node vSAN Deployments; Two-Node Cluster Requirements