NIS/NYS Setup

5.12 NIS/NYS Setup

NIS/NYS Setup

The basic content of this section was donated by Grant Taylor. It was edited for clarity and space. Other content was contributed by users on the redhat-list mailing list.

This text attempts to describe the yp, NIS, and NIS+ support offered in Red Hat Linux products.

What is yp? NIS? NIS+? NYS? These questions are answered in the NIS-HOWTO. It is included with Red Hat Linux in the ldp package and on the CD. If you install the ldp package, you will find the NIS-HOWTO in /usr/doc/HOWTO.

The quick answer is that while yp ("Yellow Pages") is the phone book in Britain, NIS is the traditional RPC-based implementation for sharing passwd, group, hosts, services, and other useful things between many machines. NIS+ is a snazzier, and more secure implementation of the same idea. NYS is the public domain version of NIS.

What is offered? Red Hat ships NYS client code in its libc and plain yp/NIS client programs like ypcat and ypbind. We ship a plain NIS server daemon, since the NYS (aka NIS+) server daemon is not yet ready for prime-time. Our ypserv does not appear to have the tcp_wrapper-style /etc/hosts.allow/deny checking compiled in.

How do I get ypbind to work properly? How do I set up a client workstation?
The NYS code in libc does it all. There is no need to run ypbind. You probably /em do need to run domainname (apparently for the benefit of of plain NIS client programs). You must configure which maps are read from where in /etc/nsswitch.conf, and which NIS server and domain you are in using /etc/yp.conf. nsswitch.conf is well commented, and yp.conf will look like this:
domain foo ypserver foo.bar.com
Do not put the usual +:::: lines at the end of passwd or group.
How do I run ypserv (master)? Red Hat ships a plain NIS (a.k.a. yp) server. It works just like any other ypserv---modify the Makefile in /var/nis to taste, perhaps move the source files into /var/nis/src, or perhaps not, run make to make the databases, and run ypserv. Further documentation is in /usr/doc/ypserv*/*.
Where are yppasswd and yppasswdd? They are not included in Red Hat Linux, but you can obtain the regular NIS distribution and install it yourself without too much hassle. It is available from the places listed in the NIS HOWTO. You have to modify the pwupdate script that comes with it, even though the README claims it works with the NYS Makefile we ship. We also don't ship a rpcsrv/yppasswd.h, although we do have the .x file. The yppasswdd package comes with both so it doesn't matter much. The NYS define should be used, but don't use the -lnsl library since it is built into our libc.
This information is miserably incomplete! There is already an NIS-HOWTO that describes how to set things up far better than this document does or should. It is also included with Red Hat Linux in the ldp package.