HP StorageWorks D2D Low-bandwidth Replication Software
HP StorageWorks D2D2500 and D2D4000 backup systems are virtual tape library appliances designed to fit into your existing tape backup infrastructure using standard tape backup applications (for example, HP DataProtector) and provide several benefits over a pure physical tape policy:
- Faster restore times due to backup data remaining onsite and on random access media (disk).
- Better backup automation by reducing the need for physical tape media and the tape handling that it entails.
- Backup consolidation by backing up multiple servers to virtual libraries on a single appliance.
In addition to these benefits, HP StorageWorks D2D2500 and D2D4000 backup systems also provide data deduplication technology which is a form of single instance storage and this allows a greater history of backup data to be retained on disk. HP's dynamic deduplication uses inline processing, hash-based chunking. This works by analyzing the stream of data as it is backed up from any backup application, the data is divided up into small but variable sized (approximately 4 Kb) 'chunks' and on the fly each chunk is compared to all previously stored chunks then stored on disks if unique or referenced in the backup, if it already exists on disk. After deduplication, each chunk is then compressed using a conventional compression algorithm.
The result of data deduplication is that the first full backup of a server will be stored almost in its entirety except that a small amount of deduplication of chunks will occur within the initial backup. Subsequent full backups of a server will store only the additional chunks of new or changed data (for example, parts of changed files or newly created files).
The result of deduplication is that tape rotation schemes (for example, GFS) which would have traditionally resulted in large amounts of duplicate data being stored on disk (or tape) now take up only the disk space of the last full backup and any unique data that existed in previous backups but has now been removed. This means that many more backup versions can be retained with no penalty on disk space.
When restoring data using the backup application, the original backup stream is reconstituted from all of its constituent chunks and returned to the application. In this way, the backup application has no visibility that the data has been deduplicated and also no dependency of HP StorageWorks D2D2500 and D2D4000 backup systems to know anything about the backup application data format.
||HP StorageWorks D2D Low-bandwidth Replication Software
||StorageWorks Replication Solutions Manager
|Operating System Support
||1 Disk Array
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