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Exam objective 2.209.2 has a weight of 3 and verifies that candidates are able to export file systems using NFS. This includes access restrictions; mounting an NFS file system on a client; and securing NFS. You should be familiar with the configuration files, the tools, and how to set restrictions and mount options. It is common for a computer to be both an NFS server and an NFS client. To be a server, a computer must have the NFS daemons running and it must export one or more directories to other systems. To export a directory is to make it available. This system exports one. You can export any directory on your file system. This is my home network, so I'm not concerned about security, so I've just exported the root directory as you can see here. This is the address to which it is exported. Only computers with a matching address will be allowed to access the directory. You can use wild cards to specify a subnet, or as I've done here, us a slash to specify a range of values. You can also use host names instead of IP addresses. This specifies that the file system is to be exported as read-write. Sync means that NFS is to respond only after a command has been executed. This is the default in the current versions of NFS, but that is a change from version 1 and if you don't specify it you'll get a message. The no-root squash option means that a user with root permissions will retain those permissions in this file system. There are a number of options that are available and they all have to do with security. Once you have defined your exports, you need to let the daemon know by executing the export FS process with the A option. This way, any changes you made to the export table are recognized by the Mount daemon, and on a server you could always check to see which computers have mounted the server's file systems. The Shell Mount program lists them for you. It has some options, so you can find out more information if you need it. That's about it for an NFS server, but this computer also acts as a client. The first step in setting up an NFS client is to add an entry to fstab. In this entry, the remote computer, the server, is named ARLIN, and it has exported the root directory. This is the name of a local directory here on the client; the one to be used as the mount point. It is to be an NFS file system mount. You see, it doesn't matter what kind of file system it really is, because this client is only going to talk to the NFS server on the other end. And the mount is to be of a read-write file system. The Mount command with the A option will attempt to mount everything listed in fstab. If any of the mounts fail you'll know about it right here. As you can see, one of the host names is unknown. That's because it has not been included in the host file yet. But the other file system's all mounted. This is the root directory of the mounted file system on the server named ARLIN. You need to know how to secure the system. You need to review the MAN page for exports and see the sort of things you can do to secure exported file systems.