Storage Management

NetWare has a universal file system; it supports DOS (FAT), Macintosh (HFS), Unix (NFS), and OS/2 (HPFS) name spaces. As the file system evolved with each version of NetWare, vendors of backup software had to scramble to catch up.

Novell's solution to this problem was SMS (Storage Management Services), which abstracts storage data structures and uses TSA (Target Service Agents) to export data. TSAs typically export file system data but can work against any kind of data store--NetWare 4.0, for example, included a TSA for the global directory.

To encourage broader uses of SMS, Novell in partnership with Palindrome (Naperville, IL), a vendor of storage management software, has undertaken to port SMS to non-NetWare platforms. Given a generic SMS framework, says Palindrome's vice president of technology, Jim Gast, database vendors can create TSAs that understand table and row locking, and E-mail vendors can create TSAs that work with names meaningful only within message stores. ``When you back up a message store with native file system names,'' says Gast, ``you have no clue how to restore just one person's E-mail, because objects don't have names that are natural to the user of the restore utility.''

Along with improved SMS support, NetWare 4.0 offered an embryonic HSM (hierarchical storage management) capability. In its first incarnation that technology, which came from Imagery Software (Bedford, MA), a Kodak subsidiary, was specific to MO (magneto-optical) jukeboxes and the HCSS (High Capacity Storage System) designed for such devices. With HCSS, a vast quantity of image (or other) data can reside on a relatively small NetWare volume backed by an optical jukebox. Files not recently used migrate to optical storage; when requested, they migrate back. This application was the first to use NetWare's real-time data migration module; the next was CDISC, which caches NetWare-mounted CD-ROMs. It did not, however, use the SMS storage management data redirector, so SMS-enabled archival disk-grooming and HCCS-enabled file migration--though conceptually similar--remained two separate activities.

Imagery Software has developed an HCSS successor called MSS (Mass Storage Service). ``HCSS was a jukebox manager,'' says John Hoye, marketing manager for Imagery Software, ``but jukeboxes are just one place that MSS can migrate files to.'' The other place is the hard disk.

With MSS, files from a group of small departmental servers can spill over to a single superserver and from there to an optical jukebox. But there's still no connection between HSM and SMS. ``I've always felt that HSM and SMS are solutions to the same problem,'' says Gast. ``One set of data replication primitives should support all the different scenarios in which you move data from point A to point B--mail, directory synchronization, archiving, and HSM.''

He's right. Novell today solves these problems using four different technologies that cry out for integration. Because NetWare lives close to the hardware, it can pump a lot of data in a hurry. That capability, packaged as a standard data-migration service, would make Novell networks more attractive to a large and growing number of applications.

As the data itself evolves from raw files to structured documents and objects that bundle code and data, the file system needs to follow suit. Here, too, there's more than one approach to the problem.

In the realm of document management, the latest versions of WordPerfect, GroupWise, and SoftSolutions support the ODMA (Open Document Management API) (see ``Managing the New Document,'' August 1994 BYTE), which enable ODMA-aware clients to bypass the raw file system and place documents under the control of ODMA-compliant repositories. SoftSolutions support for DEN ( Document Enabled Networking), a Novell/Xerox-companion effort that splits monolithic repositories into component services (e.g., storing, indexing, and converting), is also forthcoming, according to Alvin Tedjamulia, director of research and strategic planning for Novell GroupWare.

OpenDoc's Bento, another document storage technology, is tuned for single-user compound documents. If Novell succeeds with its OpenDoc for Windows effort, ODMA- and DEN-oriented document managers (e.g., SoftSolutions) will want to accommodate Bento-aware clients by directly implementing Bento structured storage and versioning or mapping Bento's APIs.

More generally, Novell aims to evolve NetWare's file system. ``Apply NDS technology to a file map,'' says Joe Firmage, general manager of Novell's Network Development Tools division and vice president of strategic planning for the NetWare System's Group, ``and you get an enterprise-wide attributed data store.'' Novell's Cairo? Exactly, says Firmage, ``but we already have the network infrastructure today.''