Managing Hierarchical File System Data Sets
A hierarchical file system (HFS) data set is a data set that contains a POSIX-compliant hierarchical file system, which is a collection of files and directories that are organized in a hierarchical structure that can be accessed by using z/OS® UNIX. You can use many of the standard BSAM, QSAM, BPAM, and VSAM interfaces to access data in z/OS UNIX HFS files. Most applications that use these access methods can access HFS files without reassembly or recompilation.
The contents of HFS data sets are structured like a tree, based on a root directory with various subdirectories. The files within an HFS data set are identified by their path and file names.
DFSMShsm can automatically back up HFS data sets if it is using DFSMSdss as its data mover, but it cannot back up individual files within an HFS data set.
- Deciding which DASD devices will contain the HFS data sets.
- Deciding how to control access to them.
- Structuring the file systems.
- Determining backup, restore, and expiration date policies.
- Determining HFS naming policies (file names can be up to 255 characters long and path names can be up to 1023 characters).
- Defining data classes, management classes, and coding ACS routines and JCL statements for HFS data sets.