This worked well:

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.5/html/Administration_Guide/sect-Preparing_and_Adding_NFS_Storage.html

References:

http://200.1.19.60/ovirt-engine/docs/manual/en-US/html/Administration_Guide/sect-Preparing_and_Adding_NFS_Storage.html