This is a mini-guide for setting up an NFS-share between two computers with full write access.
First off, you need the necessary NFS-packages. In Debian, these are calles "nfs-common" and "nfs-kernel-server".
Change this line to your needs and add to your /etc/exports file on your server machine.
/home/tux 192.168.0.0/255.255.255.0(rw,no_subtree_check,all_squash,async,anonuid=0,anongid=0)
The subnet mask (after the "slash") defines how close the client's IP has to be to be able to mount the share. In this example, only the last of the four numbers may differ. If you just want a single client with a static IP to be able to mount, just enter the IP and skip the slash and the subnet address.
To make the share accessable on the network, the NFS server needs to be restarted. In Debian, this can be made by:
/etc/init.d/nfs-kernel-server restart
The client machine also needs some of the NFS-software. In Debian, only the "nfs-common" package is needed.
Now, you can mount the share manually, simply by a mount command, like:
mount -t nfs 192.168.0.1:/home/tux /mnt
However, you'll probably want an automatic mount every time the computer boots up. This can be done by entering this line to your /etc/fstab:
192.168.0.1:/home/tux /mnt nfs _netdev,auto,user,hard,intr,exec 0 0
"/mnt" represents your mount point. "_netdev" makes the mounting occur after the network is initialized. Note that you can mount a directory lower in the directory tree of the share, i.e. /home/tux/files.