CA 7 r12.0 can accommodate up to 999 libraries to be defined in the INIT File. Leading zeros are required only for CA Librarian data sets.
INDEX number 254 is reserved for the override library, and 255 is reserved for the HELP data set. The default JCLID on the DB.1 panel is zero. We recommend that you give one JCL data set an INDEX value of zero so that the DB.1 panel JCLID field is not required for jobs with JCL residing in that data set. This is also applicable to the Parmlib field on the DB.11 panel. The PARMLIB in the DB.10 panel has no default value because it is optional.