Back-up tools for Office 365

Now that NGSC is robust (https://techcommunity.microsoft.com/t5/OneDrive-for-Business/My-compliments-to-One-Drive-for-Business-Next-Generation-Sync/m-p/22238#M405) you can have a full synchronized copy of each users' ODFB on their local PC.  I use Carbonite to backup each ODFB full data set to their cloud every day.  Carbonite keeps multipe versions of files for up to 3 months, in case you accidentally delete something.  In conjunction with that, once a quarter, I back up each local ODFB to a folder on a USB 3.0 hardware encrypted hard drive, which will never be used again.  (The folder will never get overwritten.  Additional versions of the folder are added each quarter as space permits).  So, I always have a point-in-time backup that captures everything on ODFB before anything is deleted by Carbonite.  Here's the hard drive that I use:  http://shop.lenovo.com/us/en/itemdetails/0A65621/460/DD2DC2671912409D84A59A3EABAD4044

Since these backups never get overritten, the drive will eventually fill up and need to be retired and replaced.  You can safely leave them running overnight, because they keypad on the drive accepts a robust encryption key so, if it gets stolen, it will be difficult for them to access the data.

Carbonite is $60 per year per user, so not onerous for a small business, and well worth the backstop.  The encrypted drives are around $200 each.  Don't know how many you'll need.  Depends on space requirement but, again, a valuable backstop.