Chapter 21: Managing Linux on Your LAN

Overview

Now that you ve learned the networking theory in Chapter 20 , you re ready to put that theory into practice on your Linux computer and network.

First you ll learn some of the basics of network hardware. Hubs connect the different computers in a LAN. Switches segment a LAN, which help you regulate traffic within your network. Routers serve as a junction between networks, directing traffic as needed.

Next, on a Linux computer, you need to configure your network card and make sure it s connected to the proper network card address by using the ifconfig and arp commands. Various commands are available to configure the hostname of your computer on a regular as well as a Network Information System (NIS)-based network. If you ve set up Red Hat Linux correctly, the appropriate network settings should show in files such as /etc/ hosts , /etc/host.conf , /etc/sysconfig/network , and /etc/resolv.conf .

As we continue, you ll learn to configure a LAN with IPv4 private addresses. One reason why IPv4 addresses are still in common use is that they allow you to easily configure a LAN. With the right routing configuration and one public IPv4 address, you can connect this LAN to the Internet.

Red Hat Linux includes some tools for connecting your computer to the Internet. While some are graphical, others require only the command-line interface. These tools include Red Hat s own Internet Configuration Wizard and minicom .

Finally, if you have problems with your network, commands are available to help you troubleshoot any problems that might arise. The netstat command lets you measure traffic through different TCP/IP ports. The ping command enables you to check connectivity. And finally, the traceroute command helps you visualize the route that your messages might take through diverse networks, especially the Internet. This chapter covers the following topics:

• Understanding routing, switching, and hubs

• Configuring your computer on a LAN

• Configuring private and public networks

• Creating Internet connections

• Troubleshooting your network