Best way to load balance MQTT is cluster or Bridge and why

Question

One or more MQTT brokers could be bridged together. Bridge forward PUBLISH message from one broker node to another. [1]

Clustered nodes will share/copy the same topics tree, but bridge nodes will not.

What is the protocol used to share the same topics tree in a cluster ? Is it HTTP ? is it disadvantage ? Because MQTT is a light weight protocol compared with HTTP

1. https://github.com/emqx/emqx/wiki/Bridge

Answer 1

Erlang/OTP, TCP communication between clusters. Best way is using cluster.

                              ----> Node1
                              ----> Node2
-----> Nginx/HAProxy/AWS SLB  ----> Node3
                              ----> Node4
                              ----> Node5