Red Hat Enterprise Linux 5 Administration Unleashed

Enabling NIS 261/var/yp/nicknames file for a complete list of aliases set up by default. From the client, theypwhich -x command lists the available nicknames. Remember to run the make commandin the /var/yp/ directory on the server after modifying the /var/yp/nicknames file toupdate the NIS map file for it.The ypserv service also has a configuration file, /etc/ypserv.conf. The default filecontains comments that detail the available options. The ypserv.conf man page providesdescriptions of them as well. Access control lists can also be added to this file. Refer to the“Restricting Access to NIS Server” section for details.12The yppasswdd daemon allows users on the NIS clients to change their passwords and otheruser information stored on the server. Refer to the “Connecting to the NIS Server” sectionfor instructions on using the client-side utility. When passwords and user information arechanged with yppasswd, the daemon assumes the /etc/passwd and /etc/shadow files bydefault. If the server uses different file locations, set them in /etc/sysconfig/yppasswdd.This configuration file also contains an option to pass arguments to the daemon when it isstarted. A list of these arguments can be found in the yppasswdd man page.Adding Optional NIS Slave ServersThe NIS server where the master copy of the user information is stored and can be modifiedis called the master server, and each NIS domain can only have one master server.However, slave NIS servers can be added to the network.These slave servers retrieve their data from the master server and are useful if the masterserver fails or needs to be taken down for maintenance; the slave server can act in itsplace. NIS clients will try to find a different server for its NIS domain if the server it isconnected to is responding slowly or not at all. If slave servers for the domain exist, theycan help handle the heavy request load.Configuring NIS Slave ServersTo configure a slave server, first configure the master server for the domain. If slaveservers are to be set up for the domain, the ypxfrd service can be run on the NIS server toallow for NIS database transfers. Start it on the master server as root with the serviceypxfrd start command. Also, make sure it is started at boot time with the chkconfigypxfrd on command, also as root.Also on the master server, add the hostname of the slave server to the list of NIS serversin the /var/yp/ypservers file. Enable this change by switching to the /var/yp/ directorywith the cd /var/yp command and running the make command as root. Make sure thehostname of the slave server is in /etc/hosts or can be resolved via DNS.The same set of RPM packages required on the master server must also be installed oneach slave server. Make sure the hostname of the master server can be resolved to its IPaddress on the slave server via DNS or the /etc/hosts file. Then, copy the NIS databasesfrom the master server by executing the following as root on each slave server, where is the hostname of the master NIS server (on a 64-bit system, the lib directorywill be lib64 instead) :/usr/lib/yp/ypinit -s