ESX supports using NAS through the NFS protocol. The NFS protocol enables communication between an NFS client and an NFS server.

The NFS client built into ESX lets you access the NFS server and use NFS volumes for storage. ESX supports only NFS Version 3 over TCP.

You use the vSphere Client to configure NFS volumes as datastores. Configured NFS datastores appear in the vSphere Client, and you can use them to store virtual disk files in the same way that you use VMFS-based datastores.

Note

ESX does not support the delegate user functionality that enables access to NFS volumes using non-root credentials.

NFS Storage depicts a virtual machine using the NFS volume to store its files. In this configuration, the host connects to the NFS server, which stores the virtual disk files, through a regular network adapter.

NFS Storage
The host connects to the NFS server, which stores the virtual disk files, through a regular network adapter.

The virtual disks that you create on NFS-based datastores use a disk format dictated by the NFS server, typically a thin format that requires on-demand space allocation. If the virtual machine runs out of space while writing to this disk, the vSphere Client notifies you that more space is needed. You have the following options:

Free up additional space on the volume so that the virtual machine continues writing to the disk.

Terminate the virtual machine session. Terminating the session shuts down the virtual machine.

Caution

When your host accesses a virtual machine disk file on an NFS-based datastore, a .lck-XXX lock file is generated in the same directory where the disk file resides to prevent other hosts from accessing this virtual disk file. Do not remove the .lck-XXX lock file, because without it, the running virtual machine cannot access its virtual disk file.