HSM for Windows client overview
The IBM® Storage Protect HSM for Windows™ client provides hierarchical storage management (HSM) for Windows New Technology Files System (NTFS) and Resilient File System (ReFS) file systems.
The figure shows an overview of hierarchical storage management.
HSM is a data storage system that automatically moves data between high-cost and low-cost storage media. HSM exists because high-speed storage devices, such as hard disk drives, are more expensive per byte stored than slower devices, such as magnetic tape drives. You can use HSM to store the bulk of your enterprise's data on slower devices, and then copy data to faster disk drives only when needed.
In effect, HSM turns the fast disk drives into caches for the slower mass storage devices. The HSM for Windows client monitors the way files are used and automates policies for migrating files to slower devices.
The HSM for Windows client manages the migration of individual files, files from parts of file systems, or complete file systems, to remote storage in IBM Storage Protect. Migrated files can be accessed, opened, and updated by the Windows application corresponding to the file extension.
- An administrator can define migration jobs for each volume. The job can include or exclude files of a certain file type (extension). Files can be included or excluded depending on file age or size. The files that are eligible for each migration job can be stored in separate file spaces in IBM Storage Protect storage.
- An administrator can define recall quotas to limit the number of file recalls during a specified time period. Quotas can apply to the entire system, to user groups, or to specific users.
- The HSM for Windows client can also be used for archiving purposes. In this case, files are migrated to IBM Storage Protect storage and the original files are either kept on disk or deleted.
- Search and retrieve options are available to the administrator for migrated files. Selected files or complete file spaces can be retrieved either to their original location in the file system or to a different location in the file system.
- When migrated files are recalled and changed by a user, several versions of a migrated file are kept in IBM Storage Protect storage until the file system is reconciled. A user recall always accesses the latest version of a file. However, an administrator can retrieve any available version of a file.
- Threshold migration monitors file-system space usage and migrates files when space is needed.
- Threshold migration migrates older and larger files from your file system. You configure whether file age or file size is a better qualifier for migration.
- You can move migrated data without interrupting HSM services.
You can move migrated files to accommodate the changing needs of users, applications, and hardware. For example, if a user moves to another site, you can move the migrated data. If a new or changed application requires that data is moved to another location, you can move the migrated files. You can maintain HSM services without recalling and migrating the files again.
You can replace or rename a volume or file server and maintain HSM services without recalling and migrating the files again.
- The scope of individual migration jobs can be limited by the number of files and data volume.
- Individual jobs can be run at different times.
- Migration jobs can be organized according to the logical structure of a volume (including different parts of the directory structure). Jobs can reflect the structure of an organization or user groups.
- Migration jobs can be organized according to different types of files such as office documents, images, and text files. This organization provides a more logical view on data than traditional HSM.
- Threshold migration can automatically prevent your volumes from running out of free space.
- With threshold migration's age weighting, active files are kept on the volume. Less-active files are migrated to IBM Storage Protect storage.
- With threshold migration's size weighting, larger files are migrated to IBM Storage Protect storage. Larger files provide a more efficient migration.
- You can implement migration jobs and threshold migration on the same volume. You can build a policy that is based on both file values (migration jobs) and space usage (threshold migration).
The HSM for Windows client comes with a graphical user interface (HSM for Windows client GUI). You can use the HSM for Windows client GUI to define and run migration jobs, threshold migration, reconciliation, searches and file retrieval, and to define general settings. You can also do many of these tasks by using HSM for Windows client commands from a Command Prompt window.
The HSM for Windows client supports local, fixed NTFS and ReFS file systems. Microsoft® Cluster Server (MSCS) cluster volumes are supported, if they are formatted in NTFS or ReFS. Windows File Allocation Table (FAT) partitions, Common Internet File System (CIFS) shared folders, network-attached storage (NAS) drives, and other file systems are not supported.