Distributed name services

Programs and protocols that use TCP/IP to route data, Mail Transfer Agents such as MMDF, remote terminal login programs such as rlogin, and PC connectivity packages such as PC-Interface need the ability to map IP addresses to machine names and vice versa.

Name services provided by the SCO OpenServer Desktop and Enterprise systems to facilitate this mapping include:

The hosts file

The /etc/hosts file lists pairs of machine names and IP addresses. Update this file on each machine when a network is small, relatively stable (adding or removing machines infrequently), and not connected to the Internet. See the manual page for hosts(SFF) for more information.

You can use the TCP/IP utility, rdist, to distribute /etc/hosts to a list of designated machines on your local network if the network grows to the extent that editing individual files becomes a burden. See ``Distributing files remotely over TCP/IP'', and the manual page for rdist(TC) for more information.

Domain Name Service (DNS)

Use DNS to create, maintain, or access a distributed database of names and addresses. These capabilities become critical as your network grows larger or if you connect to the Internet. Many other programs, such as web browsers and various Mail Transfer Agents, either require or make effective use of DNS. See ``Configuring the Domain Name Service''.

Network Information Service (NIS)

Use NIS to serve /etc/hosts data to diskless or dataless NIS clients, or to serve other NIS clients where restricted access to the actual /etc/hosts file is desirable. See ``Configuring the Network Information Service (NIS)'', for more information.

Administering a name service

Common tasks associated with name services include:

• adding, removing, and changing machine names in the system's name service database (/etc/hosts or DNS databases).

• distributing updated information to remote machines by manually copying files or distributing files with NIS or rdist.

• tuning DNS configuration.