Advanced NIS administration

Creating and modifying non-default maps

To update a non-default map, you edit its corresponding ASCII file. Then you rebuild the updated map using the /usr/sbin/makedbm command (for more information, see the makedbm(1Mnis) manual page). If the map has an entry in the /var/yp/Makefile, run ypbuild as described in ``Making the maps''. If the map does not have an entry, create one following the instructions in ``Making the maps''. Using ypbuild is the preferred method. Otherwise, you will have to run makedbm yourself.

There are two different methods for using makedbm:

Redirect the program's output to a temporary file, modify the file, then use the modified file as input to makedbm.
Have the output of makedbm operated on within a pipeline that feeds into makedbm again directly. This is appropriate if you can update the disassembled map with either awk, sed, or a cat append.

You can use either of two possible procedures for creating new maps. The first uses an existing ASCII file as input; the second uses standard input.

NOTE: In all cases, if /var/yp resides in an s5 file system, you have to create an alias for the map to deal with the 14-character limitation for filenames (which, in the case of map names, is actually an 8-character limitation because of the suffixes that makedbm creates). To do this, change directory to /var/yp and enter:

echo mapname `/usr/sbin/ypalias mapname` >> aliases

Note also that, for the command ypwhich -m to work properly, the contents of the /var/yp/aliases file must accurately reflect the contents of the /var/yp/domainname directory.