I'm a little paranoid about possible loss of data, and over the years I've spasmodically backed up valuable files like photos and documents. The problem with those backups is that I never seem to make them in a timely manner. In an attempt to remedy that problem, I've installed a Synology DiskStation DS411j NAS. This "computer" can accept four hard drives for a total storage of 16TB. I have it configured so that each file stored on this device also has a duplicate copy of it on a different drive. This device has an assortment of drives I've used in the past, so the current storage capacity, before redundancy, is about 1.8 TB. I used to think that was enough storage for all of my data. But, guess what? Data requirements seem to increase all the time. This DiskStation makes it very easy to increase that storage. All I have to do is remove one of the four drives (usually the smallest) and insert a newer, larger capacity drive. The DiskStation then automatically brings the new drive into the system, and my newer capacity is then available. This storage is available for all devices on my network, so I can use it for data from those devices, as well. The DS411j constantly checks the health of all the installed drives. When any drive starts to degrade, the system will alert me so that I can replace the questionable drive. Remember - ALL DRIVES FAIL! It's just a matter of "when".
So, how do I make sure my newest data files are backed up on a regular basis to the DiskStation? I've tried numerous software (and there are MANY solutions available). Some of you who perform this exercise probably have your own favorite, but my current solution is SyncBack. I use the free version at this time. I have my backup automatically made once a week. SyncBack looks at the source drive and compares it with the DiskStation to determine changes. It then updates the DiskStation based upon criteria selected by me. Very slick.
Why did I choose Synology when there are so many other solutions? It boiled down to: a pleasing looking enclosure; quiet; auto drive shutdown when not in use; 4 drive capacity; features; cost. My experience with several NAS solutions has not been totally successful, consequently I quickly narrowed my choices to Synology and Drobo. It's almost a toss-up, I think. However, the Synology solution has been good so far.