To add a new class to the dynamic CDT, use the RDEFINE command to add a profile to the CDT class. An important attribute of every CDT entry is its POSIT value. There are 1024 possible numeric POSIT values. You can specify POSIT values 19 - 56 and 128 - 527. However, certain POSIT values are reserved for IBM® use.

Restriction: POSIT values 0 - 18, 57 - 127, and 528 - 1023 are reserved for IBM use and should not be used for your dynamic class entries unless you intend to share SETROPTS options with an IBM supplied class. (For example, you might choose to have an installation-defined CICS® class share SETROPTS options with an IBM supplied CICS class.) If you use a reserved POSIT number that is not currently used for an IBM supplied class, be aware that in the future IBM might create a supplied class with this POSIT number. If this conflict occurs, processing results for your class will be unpredictable.

Classes with the same POSIT value are administered as a single class when you specify a class option, such as CLASSACT or RACLIST, on the RACF® SETROPTS command or grant CLAUTH authority to one of them. You would add a new class with a unique POSIT value when you want to administer it separately from any other class.