Name service is a fundamental service of a Linux network. A name service converts text-based hostnames to the numeric IP address required by the network. In the same way that the services in Chapter 3 needed user IDs (UIDs) and group IDs (GIDs) to identify users, networks need IP addresses to identify computers. Domain Names System (DNS) is the tool that maps hostnames to IP addresses for the network.
DNS is implemented on most Linux systems with the Berkeley Internet Name Domain (BIND) software, which is the most widely used DNS software in the Internet. Linux is a fairly new operating system, but it benefits from the fact that it can run venerable software packages such as BIND that have a very long history with many years of debugging and refinement. Linux developers wisely used these tried-and-true packages for the most critical network servers.
E-mail is another critical service that must be provided by every modern network, and most Linux systems use sendmail, which is the most widely used SMTP mail server software, to provide e-mail service. In the next chapter, we configure an e-mail server using sendmail.
Was this article helpful?