Sierra: Timemachine backup routinely

This happens on basically every version of OS X, and anything that is network attached. The issue is basically that any interruption of network connection will potentially cause minor data corruption in the backup. OSX then detects the corruption, and starts a whole new backup. 

There is no good solution to this, but here's a "bad" solution that seems to work. 

1) Create a sparse bundle on your BTRFS protected volume using diskutil, make it large, but not excessively large. Something like 3x the size of your Mac's hard drive is fine, but keep it significantly smaller than the free space on the readyNAS.

2) Mount the disk by double clicking it, rename if you want. 

3) From the terminal run: sudo tmutil setdestination /Volumes/<name of your volume>

4) Now let time machine run a complete backup. 

5) Make sure snapshots are on for your BTRFS volume

Now, this doesn't solve the problem, but by placing the sparse image in a place where it will be snapshotted, should the problem recur, you can always just copy the version from the last good snapshot (essentially resetting it to a day or so ago, before the problem), and continue from there. 

You need to use the terminal because time machine doesn't let you back up to a disk image like thiis natively, so you have to force it. But that being said, it does work. 

Netgear could help solve this whole problem by adding snapshots to the volume where they store the default time machine backups, and allowing (maybe a button?) people to pull a time machine from the snapshots if needed. Until then, you'll need to do this yourself. 

This approach is better than using the default time machine setup anyway, as it will also enable bitrot protection, so you'll be protected against all manner of silent data corruption.