Earlier quoted context omitted.
...and tested. I only had to see one machine "that was being backed up" unable to restore from backup. Wasn't mine, but was enough to teach me to test them.
Absolutely! You're preaching to the choir here. However, that said, over ~3 decades I've found that having a successful rsync exit code and alerting when that is not true, along with periodic "full" rsync checksum runs, is effectively a failsafe way of ensuing a good backup. For our less critical systems, this plus "spot checking" by regularly going in and looking at "what did this file look like a few weeks ago" (so…
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