Hi, I'm using the MQTT node to send data to a cloud server, the Node-Red server is installed in a Physical Device which is collecting data from a PLC. In the MQTT out node configuration I'm using QoS 1 and I noticed that when the internet is disconnected on the device that has the Node-Red server in…

Actually IIRC from that thread - my conclusion was that Node-RED will give up eventually before running out of memory

The problem on that thread turned out to be a hardware issue, nothing to do with MQTT. I have not seen any evidence that it will buffer for ever till it runs out of memory, certainly not on QOS 1. When you say the data is sent all at once, is that multiple messages on a single topic or 1 message e…

Multiple messages on the same topic at the same time, so what do you mean is a hardware issue? that depends on how much free memory the device in which the node red is installed have?

I did not say your issue was a hardware related, I said the thread linked to turned out to be a hardware problem with that system. How long is your network disconnecting for? If you look at the mqtt out node you will see that when the network is disconnected the nodes still shows connected for up …

MQTT node with disconnection - Node-RED

General

ristomatti 13 July 2020 08:39 2

Welcome to the forum? Did you try searching the forum first? There was a discussion about this just recently: Mqtt out node buffering. There's no exact answer there but it appears it will buffer messages until the memory runs out.

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MQTT node with disconnection - Node-RED

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