5.1.2.1 - The repository shall have mechanisms in place to ensure any/multiple copies of digital objects are synchronized.
Supporting Text
. This is necessary in order to ensure that multiple copies of a digital object remain identical, within a time established as acceptable by the repository, and that a copy can be used to replace a corrupted copy of the object.
Examples of Ways the Repository can Demonstrate it is Meeting this Requirement
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Explanation
SP does not have an online mirror site for its content, so it does not use online synchronization. TSM backup copies are synchronized with copies in archival storage by regular replication from a known good copy. The TSM backup system has a database that associates tape backup copies with their originals in the Pillar storage array. The Backup Plan describes how SP creates and manages backup copies.
Relevant Document