The threat to that is a silent encryptiion on that goes on for weeks before the alert/ransom is demanded. Your mirrors are now full of encrypted trash, or you

The threat to that is a silent encryptiion on that goes on for weeks before the alert/ransom is demanded. Your mirrors are now full of encrypted trash, or you need to go back a month or more. This could be managed with a backup that maintains 'fingerprint' hashes of all the files, tracks the changes and alerts if there are too many, or alternatively, the user/admin litters the system with a set of canary files of the same type that should never change, and the backup system halts and alerts if any of them do. I'd like to see a utility to just check a set of canary files for changes. Anyone know of one?