An important component for preservation is to have multiple copies. The specific questions are: how many copies, how should they be stored, and where should they be located. Many people advocate the 3-2-1 rule for digital storage: three copies, stored on two different media, and one copy located off-site, preferably in areas with different disaster threats. (NARA; Library of Congress) The NDSA levels also incorporate this rule in the storage section.
The copies we have been looking at are:
Copy 1: Rosetta storage on spinning disk in the campus data center
Copy 2: Tape copies of our archive in the Granite Mountain Record Vault.
Copy 3: Internet copy, with DPN or Amazon Glacier
Copy 4: Access copy within Special Collections on M-Discs or our CMS
- Expanding NDSA Levels of Preservation
- The NDSA Levels of Digital Preservation: An Explanation and Uses.