I have built a laravel web application for a client of mine which runs on a dedicated server.
The system is a booking system, and the client needs access to this at any time during the work day. So he came to me with "What happends when I loose my internet connection?".
The solution I am going to implement for my client is that I will set up a Raspberry Pi that will run the same web application locally at their shop. So if the loose their internet connection, they can access the web application served from the Raspberry instead.
However, what I now need, is that the Raspberry at all times when it has internet connection, syncs up with the latest information about booked appointments from the live server. And when the internet connection goes down and they use the local web application to book new appointments, then I need the raspberry to tell the live application about those new hours that are booked when the internet connection comes back on.
I have been looking at replication-sets, but it looks like I need a third server to be a judge here for the system to work in such a way that the slave gets writing capabilities to its mongdb server.
Can anyone help me out with any ideas here?