NFS, or network file system is another file system in vCenter. It is commonly used by NAS (Network attached storage). Similar to VMFS NAS supports file locking so that only one host can access a VMs files at a time, host 2 doesn’t need to access the files of a VM running on host 1. Overall not much to say, one thing to note is you can choose between NFS 3 and NFS 4.1, NFS 4.1 supports Microsoft kerberos authentication. It is important that all hosts on the same NFS datastore use either 3 or 4.1, separate datastore can run separate versions though.