Paradigm shift of archiving in the SAP environment
by Bernhard Morell, Senior Consultant of SAP Archiving at KGS Software GmbH & Co. KG.
Focusing on the essentials!
Those who use SAP intensively, generate a large amount of various data in the process. This data, with the absence of an archiving system, will end up in the internal SAP database. Their growth eventually leads to performance degradation of the system. At this point, if not sooner, it is advisable to think about archiving.
For SAP, an archive is exclusively a data sink in the sense of an external data storage. Access to these “outsourced” data and documents takes place via a so-called primary key – all the metadata that is necessary for a search are to be managed within SAP as the leading system. There is therefore no need for document access outside of SAP. Advantage of this philosophy: an archiving system neither requires its own logic for metadata management, nor its own authorization system.
Classic archiving systems (also known as DMS or ECM) present themselves as a ”black box”, towards to SAP and combine all the necessary components for storage management. They were eventually designed for the archiving of any process related documents beyond the SAP context and in much more detail than required by SAP
Who is responsible for access, metadata, and authorization?
Particularly disruptive, is the question of access and metadata management: Most functions are exclusively available through the client application of the archive system. However, it is exactly this function, which is not needed in the SAP environment, as it is already available through the ECL Viewer into a fully integrated SAP GUI. In order to use the full archive capabilities, it is also required that the archive system has the necessary metadata for a search outside of SAP and that a authorization system is put in place. Here conflicts with SAP are inevitable, seeing as it claims both metadata management as well as the authorization concept. In conclusion: Classical Archives, DMS and ECM systems can only be fully utilized if the integrated metadata management and authorization logic as well as the own proprietary client applications can be used.
Consequently, a new archiving approach, tailored to the SAP archiving requirements, is necessary. To understand this, it helps to take a look at the recent changes in backend storage systems. When the first archiving systems came onto the market about twenty years ago, there were only tapes for long-term mass data storage available. However, these did not meet the requirements of the archives of quick and easy access. Archive systems in these times depended primarily on optical and magneto-optical storage media. For these devices, there was no general driver. This meant that each archive system implemented its own driver and could also not depend on standards such as filing systems in storage, but rather used their own formats and storage logic. There were also no standards for media management and controlling of jukeboxes.
HSM opens doors to new archiving concept
Today, modern storage and HSM (Hierarchical Storage Management) systems take the approach of different media and media management, provide standardized filing system interfaces and also allow replication and data migration scenarios. With the introduction of these systems, new archive architectures and approaches have become possible.
The new archiving philosophy is based on the fact that each system only does what it was intended for and all other tasks are taken care of by the optimized systems created therefore. In the case of SAP archiving, these are the support of the standardized interface ArchiveLink, the performing administration of the necessary metadata for storage and management, as well as the addressing of storage systems used to optimize storage. In short: Archive systems for SAP only need a simplified structure and can do without most of the usual functions.
Division of tasks between SAP and Archive shifts
This matches a paradigm shift in archiving: The system focuses only on the optimized management of technical metadata (archive date, retention time etc.) and leaves the functional metadata such as customer name, customer number, invoice number, etc. to the SAP system. The interfaces to the data and document sources (e.g. SAP), the actual storage, and media management are transferred by the archive to the HSM system which is optimized for exactly this purpose.
The advantages for the SAP users: Existing storage systems are better utilized, the complexity of the applications is reduced and the company saves hardware since lean archives require significantly less resources. Additionally, the access speed is improved since the storage system must be optimized for this purpose, thus lowering risks associated with storage and long-term availability: storage systems can simultaneously write multiple copies on different media, control the fully automatic replication of data and they migrate data automatically and transparently to the application of new media.
This new approach can be well implemented in the area of SAP archiving seeing as a standardized interface for data and document source already exists. Furthermore, the metadata to be managed by the archiving object are minimal. The concept is also transferable to other leading or legacy systems. A number of German and international companies have already changed to this new approach and are saving significant costs compared to earlier monolithic, classic archive systems.