nis_intro - Network Information Service (NIS) introductory information
The Network Information Service (NIS) is a distributed name service that allows participating hosts to share access to a common set of system and network files. NIS allows the system administrator to manage these shared files on a single system.
NIS is intended for use in a secure environment only, where gateways do not allow outside Internet access to the NIS protocol.
In a C2 secure environment, you can run NIS in a secure mode, thereby creating secure and nonsecure versions of the NIS maps.
You can also use NIS to distribute files used by the automount daemon or to distribute other user-defined files.
Each NIS map contains a set of keys and associated values. For example, as keys, the hosts map contains all host names on a network, and as values, the corresponding Internet addresses. Each NIS map has a map name, used by programs to access data in the map.
A system's domain name is set at the time the system is booted by the /sbin/init.d/nis script using an entry in the /etc/rc.config file. System administrators can use the nissetup script to place entries in this file. The nissetup script is described in the Network Administration manual.
You can determine your system's NIS domain using the domainname command. Refer to domainname(1). A domain name is required for retrieving data from an NIS database.
Slave servers store copies of the master server's NIS maps. NIS slave servers can be spread throughout a network. Whenever an NIS map is updated on the master server, the master propagates the changes to each slave server in its domain. If the master is unavailable for any reason, the slave servers continue to make the NIS maps available to the NIS clients.
Clients are all of the systems that can access NIS maps. When a client requires NIS information, it makes a remote procedure call (RPC) to one of the NIS servers to obtain the information.
For example, the NIS map for the /etc/hosts
file in the domain market
might be stored in these files:
The makedbm command takes an ASCII file such as /etc/hosts and converts it into dbm files suitable for use by NIS. However, system administrators use the Makefile script in the /var/yp directory to create NIS map files. The Makefile script then calls makedbm.
Refer to the Network Administration manual for details on the Makefile script and other NIS management information.
Commands: domainname(1), svcsetup(8), ypbind(8), yppasswdd(8), ypserv(8), ypxfr(8)
Network Administration delim off