Little Snitch informs you whenever a program attempts to establish an outgoing Internet connection. Since Backblaze is continuously backing up and communicating with the Backblaze backup servers, Little Snitch can give frequent alerts. You can add a new rule to Little Snitch to allow the two services that Backblaze uses to communicate to stop those alerts. The two Backblaze services "bztransmit" and "bzbmenu" are found in the folder in /Library/Backblaze.
In newer releases of the product, post 2.06 the data is now located in /Library/Backblaze.bzpkg You will need to right click the backblaze.bzpkg icon and choose show contents, to access the bztransmit and bzbmenu.
Click here to view a PDF Guide to How to Allow Backblaze from Little Snitch