Assuming that you're working on one computer and want to access an installation directory on another computer over NFS, than this should be pretty easy.
Under RHEL5, NFS is enabled by default. Make sure NFS is installed on the remote computer and edit the file: /etc/exports with something like this:
# Local path IP/Subnet (options)
/data/installdir 192.168.1.0/24 (rw,sync)
Change the localpath and ip/subnet in whatever is relevant for your situation.
On the remote computer then type the command: exportfs -a to activate the new export (or restart the NFS daemon).
On the local computer mount the remote share with:
mount <hostname/ip>:/<export> <local_mountpoint>
(mount will automatically detect that NFS must be used)
Hope this helps
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