Guidelines for allocating extended-format data sets:

• Usually, sequential data striping does not require any changes to existing JCL. To allocate an extended-format sequential data set, specify EXTENDED for the DSNTYPE value in the data class.
• Usually, no changes to applications are needed to access extended-format sequential data sets.
• You can allocate extended-format sequential data sets only on system-managed volumes.
• You can allocate extended-format sequential data sets only on certain devices.

Restrictions: The following types of data sets cannot be allocated as extended-format sequential data sets:

• PDS, PDSE, and direct data sets, except VSAM
• Non-system-managed data sets
• VIO data sets.

The following types of data sets should not be allocated as extended-format sequential data sets:

• System data sets
• GTF trace
• Data Facility Sort (DFSORT) work data sets
• Data sets used with Hiperbatch
• Data sets accessed with EXCP
• Data sets used with checkpoint/restart