Looks like NFS gateway are started. (to further verify it, you can do “showmount -e” and it should show you the only export “/” with rw to everyone)
The blog you are following is for HDP1.x.
This doc is for HDP2.1 http://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.1.5/bk_user-guide/content/user-guide-hdfs-nfs-instructions.html
Thanks,
Brandon