This is revisiting the blog I wrote a while back, which showed using mongodump and mongorestore to copy a MongoDB database from one machine (a Unifi CloudKey) to another. This time instead of a manual lift and shift, I wanted a simple way to automate the update of the target with changes made on the source. The source is as before, Unifi’s CloudKey, which runs MongoDB to store its data about the network - devices, access points, events, and so on.