Backup is the creation of (also offline) copies of existing files so that they can be restored in case of destruction or accidental deletion. A file therefore exists at least twice: In the user's local file system and on HRZ backup system. If a file is changed in the local file system, a new copy is also created during the next backup. If a file is deleted from the local file system, it is no longer available in the backup system.
Archiving is the one-time copying of a file in its current state to the HRZ backup system. Archived files are not automatically changed or deleted by further archiving, even if the original in the local file system changes.
Note: With TSM, an archive is always provided with a lifetime. After this lifetime has expired, the data is automatically deleted without further warning.
If you write data to an archive and delete it locally on your system, the only version of this data is still on the HRZ backup system. If there is an error in the TSM on the HRZ backup system, there is a risk of losing this data irretrievably. An archive is therefore not always a useful backup copy of your data.