There are two types of login maps: one that contains map entries specified by the system administrator and one that contains user-specified entries.
It is conceivable that you might have two or more sets of login maps on your system. Authentication schemes require a specific ID mapping scheme. What this means, essentially, is that entries in maps that support a particular authentication scheme must have a specific format, which is dictated by the authentication scheme. If your system supports two authentication schemes, for example, and each scheme requires map entries to have a unique format, you will need to have two administrator-controlled login maps on your system.
ID mapping scheme refers to the format of a set of maps. Generally, there is a one-to-one correspondence between ID mapping schemes and authentication schemes, such that one set of maps supports one authentication scheme. When there is a one-to-one correspondence, the name of the ID mapping scheme and the name of the authentication scheme can be the same.
At the present time, cr1 is the only authentication scheme provided as part of UnixWare 7--with the exception of the traditional login/password scheme, which doesn't rely on ID mapping. The ID mapping scheme that supports the cr1 authentication scheme is also called cr1.
Administrator-specified map files are named idata. User-specified map files are named uidata. Both login map files are stored in the /etc/idmap directory, in a subdirectory named for the ID mapping scheme. Below are the full pathnames of the map files that support cr1:
Examples throughout the discussion of ID mapping assume you are setting up maps to support cr1.
The following sections describe setting up and maintaining idata and uidata map files.