Most systems attached to a network use DNS services to determine the IP address associated with a hostname. However, private hosts on your local network won't be known to your ISP's DNS server and therefore can be accessed only by IP address, not by hostname. Moreover, Samba and other local area network services won't operate correctly unless they can resolve hostnames.
Fortunately, using the Network Administration Tool, you can configure your system to determine the IP address associated with a hostname even when DNS services are not available. To do so, use the Hosts tab of the Network Administration Tool, shown in Figure 11-1.
Figure 11-1. The Hosts tab of the Network Administration Tool
To specify host information, launch the Network Administration Tool by choosing System Settings Network from the main menu. Select the Hosts tab of the Tool, click New. The Add/Edit Hosts entry dialog box appears (Figure 11-2). Specify the IP address and name of the host. If desired, you can specify one or more aliases or abbreviated names for the host. By default, the host information includes an entry for the IP address 127.0.0.1, which is associated with the hostname localhost. The Add/Edit Hosts entry dialog box does not display this entry, which protects it from accidental modification.
Figure 11-2. The Add/Edit Hosts entry dialog box