(Source: T. Mason from Zebrafish Book 5th Edition)
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We use Retrospect backup software (http://www.emcinsignia.com/) and conduct nightly backups of all our database files. We use the CD-R option within the Retrospect software and then archive the CD-R media when it becomes full. I n addition to nightly incremental backups, we record monthly "snapshots" of the database files and duplicate copies of all our files are kept off-site to secure the data.