Chapter 5. Basic Services

One of the reasons why Unix systems have always been popular is that they provide services to other computers on the network, as well as to any users who might be logged in to the machine. Back in the days when memory and disk space were expensive, it made a lot of sense for businesses and universities to have centralized computers handling things like email, file distribution, and backup storage. In a lot of cases, the "computers" on people's desks were simple dumb terminals, basically composed of a keyboard and a monitor with some way of communicating (such as a network card) with the Unix system where the users ran all of their programs.

Even though almost nobody uses dumb terminals on today's networks, it still makes a lot of sense to have at least one machine on your network providing useful services to the other computers. In this chapter, you'll learn how to start and stop your servers without rebooting, install a daemon to provide a service for everyone on the local machine or the network, install and configure a DHCP server for a small LAN, log in to a remote Unix system with Telnet and SSH, and transfer files with FTP, rsync, and Open SSH.