Backup Analysis; Physical Versus Logical Data - HP StorageWorks 12000 - Virtual Library System EVA Gateway Manual

Item Description
1 The VLS analyzes the backup as it goes through memory.
2 The backup application metadata is stripped and used to understand the format of the tape.
3 The metadata database creates a map of the locations of the logical backup data.
Figure 66 Backup Analysis
.
In Figure 67, two instances of File A are shown, one from Session 1, and one from Session 2.
At the backup object level, each version of File A is different because the metadata attached by the
backup application contains different information. However, at the logical level, these files are the same.
Accelerated deduplication strips away the backup application metadata to reveal duplicated data that
may be present in the logical data.
Figure 67 Physical versus Logical Data
.
2. Data grooming
when it is ejected to a library slot. This phase only occurs if backups are complete. The on-the-fly
backup analysis has already been performed, and the metadata database is queried to find out:
a. what new backups are on the tape
150 Virtual Library Systems
This phase is triggered when a tape is unloaded either inside a drive, or