If it takes two hours to do a backup then you are doing something wrong. Use Time Machine on a Mac, or File History on Windows, and you don't even notice that backups are happening. The occasional full system backup can be done overnight. Most backup programs can be set to shut the computer down after they have finished
Continuous incremental backups of changed files provide the most versatile backups. I used to use a similar, but slightly more sophisticated, system at work for over 500 users and could recover lost files within 10 minutes.
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