At IU, are data stored on the SDA backed up?

Due to the mammoth volume of data stored on the Scholarly Data Archive (SDA) at Indiana University, it is neither practical nor economical to back it up, at least not in the usual sense. However, two tape copies of the data are made by default to protect against random tape errors. If one tape fails, data can be retrieved from the other tape. Unfortunately, since the files are always online and visible to the users, an accidental deletion means data is irreversibly lost. The SDA in this sense doesn't have an offline, traditional backup system.

The two copies of data stored on the SDA reside at two geographically distant sites (at IU Bloomington and at IUPUI in Indianapolis), in two separate tape libraries. Also, two separate metadata backups are performed, at IUB and IUPUI. As a result, even in the event of a catastrophic disaster affecting either the IUB or IUPUI site (such as a fire or a tornado), all dual-copy data on the system would still be safe.

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