Now that the map has been transferred the client is then caught up by transmitting the AOF data to the client. At this point the client is caught up and joins without any further interruption. What if you have a huge map and the client can't process it faster than the server, never catching up? Kee...

So, the network talk is good. Thoughts on save/transfer. Would implementing a transfer method similar to Redis make since? So in Redis - redis <dot> io , when a replica requests to join, the Donor node will create a RDB file, this is a dump of the data-set as it is currently, not how it got to that ...