This tutorial by user  shows us how to get FreeNAS 9.10 and NFS set up with a datastore VMware ESXi. See the link below for the full set of instructions. 

Many choose to use NFS as opposed to iSCSI in their VMware vSphere environments.  NFS has a lot of benefits and use cases particularly when we look at the efficiency of NFS.  With NFS there is no encapsulation that needs to take place as there is with iSCSI.  Like iSCSI, NFS can use an existing IP network as well.  So, starting off simple here, let’s take a look at how to configure FreeNAS 9.10 NFS VMware ESXi 6 datastore.

Configure FreeNAS 9.10 NFS VMware ESXi 6 datastore

The specific version of FreeNAS I am using is 9.10.2 U3 and is the most recent GA version on the FreeNAS site at the time of this writing.  I am not covering here the setup of FreeNAS in general.  You will want to provision your storage and your network connectivity on the appliance itself.  For the purposes of the post, I am running FreeNAS as a VM which is a great way to play around with iSCSI and NFS in a lab.  I have setup a management IP as well as another interface that I have bound for NFS connectivity.

Configure FreeNAS 9.10 NFS VMware ESXi 6 datastore