Every article about Network Attached Storage (NAS) reminds readers that a NAS is not a backup system, even if it runs multiple drives in a mirrored RAID configuration. When I bought my QNAP NAS four years ago, I was well aware of this advice, but I chose to ignore it. I primarily used my NAS as a backup device, and occasionally to serve files. However, recent SMART scans on one of my hard drives started throwing health warnings. While this doesn’t mean immediate disk failure, it was a…