Recently, Tidbits published an article on International Verify Your Backups Day suggesting that restoring a few critical files is a good sanity check.
That’s a great idea—but it falls woefully short of proving that the data is actually intact and unmodified without errors or bit-rot.
What any professional ought to do regularly:
- Verify the entire backup (all of them) periodically, proving them to be 100% error-free, whether on a hard drive, SSD, read-only optical disc or a network.
- Restoring a few critical files after step #1 is still a great idea, just in case some other issue exists which is not about the data integrity at all (things like failing to backup successfully or backing up the wrong files, or omitting files from backup, etc).
The solution to #1 is to use IntegrityChecker, which is a cross-platform Java command line program that runs on any computer with Java (Mac, Windows, Linux, etc).
Validating data transfer integrity
IntegrityChecker is highly useful for peace of mind for any task involving data validation, data transfer, backups, etc.
IntegrityChecker can prove that a copy is identical to the original using cryptographic hashes (the basis for modern encryption).