Edit /etc/hosts and /etc/vfstab on the machine which needs the filesystem mounted.
Hosts file should have servername and IP of the host server. Your vfstab is for automounting the filesystem.
Edit the /etc/hosts and /etc/dfs/dfstab files on the server which hosts the filesystem.
Hosts file should have the servername and IP of the client system. The dfstab should have the entry for the client.
On the host system, share the filesystem:
Mount the filesystem on the client:
mount -F nfs server:/filesystem /client/filesystem/name