Configuring the Name Service Switch

The Name Service Switch determines where your system will look for host information when it needs to resolve a host name to an IP address. You can configure your system to use BIND, NIS (one of the NFS Services), the /etc/hosts file, or any combination of the three, in any order.

The default Name Service Switch configuration is adequate for most installations, so you probably do not have to change it. Figure 4-2 “Default Behavior of the Name Service Switch” illustrates the default behavior of the Name Service Switch.

Figure 4-2 Default Behavior of the Name Service Switch

Following are some suggestions for customizing your Name Service Switch configuration:

HP recommends that you maintain at least a minimal /etc/hosts file that includes important addresses like gateways, diskless boot servers and root servers, and your host's own IP address. HP also recommends that you include the word files in your /etc/nsswitch.conf file to help ensure a successful system boot using the /etc/hosts file when BIND and NIS are not available.

	CAUTION: Changing the default configuration can complicate troubleshooting. The default configuration is designed to preserve the authority of the name service you are using. It switches from BIND to NIS only if BIND is not enabled. It switches from NIS to the /etc/hosts file only if NIS is not enabled. It is very difficult to diagnose problems when multiple name servers are configured and enabled for use.

For more information on the Name Service Switch, see “Configuring the Name Service Switch”.