Data Management

HFSHierarchical File System

HFS (Hierarchical File System) allows you to store data on the IBM z/VSE mainframe in a hierarchical manner that is similar to the system used on PCs and LINUX.

  • Store and retrieve any type of data—ASCII/EBCDIC, PC file types, etc.—on the mainframe transparent to applications
  • Use longer, more meaningful file and directory names—up to 256 bytes long—including spaces and special characters
  • Updates to HFS extents can be journaled for dynamic data recovery between backups
  • Data can be moved to and from HFS using
    • FTP
    • RAAD
    • Entrée
    • Batch processing
    • User-written programs
  • HFS supports any number of sub-directory levels under each directory, provided the total path length does not exceed 256 characters. This structure is accessible from PCs, Macs, Linux instances, etc.
  • Multiple partitions and/or subtasks can access the same HFS extent for both input and output
  • Individual files within the HFS extent are locked as required to prevent collisions
  • The HFS directory can be cached, substantially reducing the number of I/Os needed to access individual files within the HFS extent
  • An individual HFS instance can have multiple DASD extents, so it can get to be quite large if desired (current maximum is ~133 gigabytes)
  • Data can be encrypted on the HFS using DES, DES3, or AES128 algorithms



HFS is an optional product that is included with your TCP/IP for VSE distribution—simply obtain a product key code for activation