Limit for SYSLIB Concatenation

ERO uses the settings you make in ERO Administration to concatenate libraries in build processing jobs. SYSLIB concatenations may contain area libraries from your release, area libraries from prior releases, and baseline libraries from joined applications.

If you have many areas in your release, and many prior releases, the number of DD statements in build processing can be large.

There is an IBM limit to the number of DD statements that are allowed in a concatenation of PDS libraries. In z/OS V1R9.0 DFSMS, the limit is defined as follows:

The sum of PDS extents, PDSEs, and UNIX directories must not exceed the
concatenation limit of 255. Each UNIX directory is counted as 1 toward this
concatenation limit. For example, you can concatenate 15 PDSs of 16 extents each
with 8 PDSEs and 7 UNIX directories ((15 x 16) + 8 + 7 = 255 extents).

ERO Administration offers you ways to reduce the number of libraries included in SYSLIB concatenations. For example, if you have many different like-load library types, you can choose to include only those library types in a SYSLIB that you need to build a composite load for a particular like-source type.