Templates
IRRTEMP2 contains database profile mappings. When your installation creates the database, IRRMIN00 reads the mappings, formats them, and writes them to the RACF® database.
RACF provides a template for each type of profile (user, group, data set, and general resource). Each profile consists of a BASE segment, plus other potential segments, for example, the DFP segment. In turn, each template contains a number that corresponds to the type of profile that it is mapping. The template maps the fields that are contained in each segment of the profile by describing the field name and field length.
If a template block is continued into another block, the last 3
bytes of the template block contains the block number of the template
expansion block. This figure illustrates how the templates would look
if Template 2 expanded into Block xxx of the database:
Figure 1. Template blocks

Attention:
Do not modify the template definitions that IBM® supplies, or unpredictable results might occur because they are not supported.