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Network Services—Local Network ServicesThe above example shows a basic TFTP file transfer scenario using FreeBSD's built-inTFTP client. The TFTP client connects to the server on localhost. In this example, Iturned on verbose output by entering the verbose command. This will tell the clientto show the transfer progress, and more details about the errors, if any. Using theget command, you can download a file from TFTP server. And once the transfer isdone, you can leave the client using the quit command.TFTP can also be used to upload files to a specific server (for example, a networkdevice backing up its configuration or OS image on a TFTP server). However this canbe a little tricky as compared to downloading files.The TFTP server does not basically allow a client to create a file on the server, bydefault. However, if the file already exists on the server, it will be overwritten.Otherwise, it fails.If you want to let your clients create files on the server by uploading files to yourTFTP servers that do not exist already, you should modify the /etc/inetd.conf file.Then add the -w parameter to the tftpd parameters. This will let the clients uploadfiles to your tftp root directory that does not already exist.If you do not want your existing files to be overwritten by TFTP clients,you should make your files read-only, using the chown(8) command(for example, permission 0440 on your files).Network File System (NFS)NFS is the original *nix file sharing protocol. Using NFS, you can share the filesystem resources (as well as printers) across a network. Hence, other hosts on thenetwork can access the remote storage, just like their local storage.NFS was developed in 1970 by Sun Microsystems, and has evolved hugely sincethen. Nowadays NFS is an integrated part of every *nix operating system.NFS is a client/server protocol, which means a server shares its storage resourcesand other client(s) can access the shared resources on the server. The clients andservers should be configured separately using FreeBSD's built-in NFS utilities.ServerNFS server has three main daemons that should be running in order to serve storageresources across the network:• The nfsd(8) daemon services NFS requests from client machines.[ 240 ]