I use several MQTT signals in my flow. What is good practice : Use a single multiple MQTT-IN node and filter out the required MQTT messages afterward Use multiple MQTT-IN nodes I am inclined to think that using a single MQTT-In node is more resource efficient, but a lot of nodes downstream will …

Hi, Take a look here :slightly_smiling_face:: [image] Multiple MQTT topics or single with switch? General Hi all! For efficiency is it better to have a single MQTT input node that receives all the topics and then add a switch to divide the topics or is it better to have …

I am not sure about @bakman2 's comment in that post. I thought that there would only be one connection to the broker for each MQTT config node, so if multiple MQTT nodes share the same server config node there would be only one connection, with multiple subscriptions. @GammaKappa do whatever you p…

In my case I am limited to the number of connections I can have to my broker. So your first example would take up 3 connections to your broker. The second example would only take 1 connection. Just somthing to think about.

[image] damica51: So your first example would take up 3 connections to your broker. I don't think that is correct. I think there is only one connection for each mqtt server config node. In both cases there will be just one of those. Easy enough to check with your broker, add more MQTT In n…

In fact I believe I can see that I am correct. On one of my PIs I have mosquitto installed as a local broker. When I look in config nodes I can see the mqtt config node [image] which tells me that I have 105 MQTT nodes using the broker. When I look in the node-red startup log I can see that the…

OK, I must be mistaken. I did not mean to give misinformation. Thanks for correcting me.

[image] Colin: which tells me that I have 105 MQTT nodes using the broker Well since you cannot have 2 MQTT clients with the same name, and those 105 nodes are all using the same client name set in the config, there must only be 1 connection to the broker. Just to make sure - netstat output …

[image] Sean-McG: since you cannot have 2 MQTT clients with the same name, and those 105 nodes are all using the same client name set in the config, there must only be 1 connection to the broker. Yes, that too.

This question pops up quite often - just making sure there is no doubt :wink:

First, thank you all for your helpful comments here. I am in the process of moving my system over to pure MQTT, and this has become relevant very quickly. For anyone else who finds this thread via search, I would like to make the case for using just one In and one Out. What happens if you have to …

Node-RED

Node-RED Forum

Efficient use of MQTT node

General

GogoVega 28 December 2023 13:15 2

Hi,
Take a look here :

Topic		Replies	Views
Flow with 10 MQTT "IN Node".. is better use just one "IN node" and split via "function node"? General	20	402	20 April 2025
Efficiency with multiple MQTT subscriptions from same broker? General	3	1727	4 November 2018
Multiple MQTT topics or single with switch? General mqtt	4	375	9 September 2023
Performance / Efficiencies - best practice? General	8	475	2 April 2020
"mqtt in" node 'Best Practice' General	14	1358	10 March 2022

Copyright OpenJS Foundation and Node-RED contributors. All rights reserved. The OpenJS Foundation has registered trademarks and uses trademarks. For a list of trademarks of the OpenJS Foundation, please see our Trademark Policy and Trademark List. Trademarks and logos not indicated on the list of OpenJS Foundation trademarks are trademarks™ or registered® trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.

Efficient use of MQTT node

Related topics