Multiple clients connection to mqtt server

Application Development MQTT
1

I have one application in ttn and 3 mqtt clients at the same time, which will connect to this server. All use the same credentional. ( I set it up under mqtt integration).
The first client works well. If the second and third client start to connect it will not work.
I can see in the wireshark trace, that the second client get a TCP connection and send in the mqtt protocol the connect command. But the ttn send an rst flag at TCP level.
If I change the second client to be the first it works.
I have 3 different server in my network. So that is the reason for 3 different clients. Because of the NAT ttn will see 3 different connection from the same public ip. Is this a problem? Or is there a limint of only one client connection to mqtt server? Can I setup different user / pwd for my clients in one application. In the Web Console ist looks like it is not passible.

Kinde regards
Hans-Jürgen

2

Yes - you are tripling the load on a free service that other people rely on.

Web hooks are OK - no continuous connection required. But the TTN MQTT broker can only do so much.

The much preferred design is for a web hook to your master and then you distribute the data to your other servers. MQTT if you have to. But not multiple clients - this sort of usage has been the direct cause of previous server difficulties.

Alternatively, talk to @rish1 about a commercial instance. I’ve not tried multiple MQTT clients on a TTI instance as, well, it’s a questionable design choice.