Unmount NFS drive in VMware ESXi

ESXi 4.x:
# esxcfg-nas -d vol_nfs

ESXi 5.0:
# esxcli storage nfs remove -v vol_nfs

Run these commands using SSH to the ESXi host to unmount an NFS drive. The post below has useful information about doing this safely.

Thanks to this post: http://www.viktorious.nl/2013/04/05/vsphere-howto-remove-nfs-datastore-from-esxi/