Next, compile and install your new kernel and reboot. Your system will now have NFS 3 server and client support built-in.

Now that our NFS server has support for NFS in the kernel, it's time to set up an /etc/exports file. The /etc/exports file will describe the local filesystems that will be made available for export, as well as which hosts will be able to access these filesystems, and whether they will be exported as read/write or read-only. It will also allow us to specify other options that control NFS behavior.

But before we look at the format of the /etc/exports file, a big fat implementation warning is in order! The NFS implementation in the Linux kernel only allows the export of one local directory per filesystem. This means that if both /usr and /home are on the same ext3 filesystem (using /dev/hda6, for example), then you can't have both /usr and /home export lines in /etc/exports. If you try to add these lines, you'll see errors like this when your /etc/exports file gets reread (which will happen if you type exportfs -ra after your NFS server is up and running):

sidekick:/home: Invalid argument