MQTT-Node Packet Size Limit?

I am working to send data using the standard MQTT node to a remote broker.
I have an issue that I believe is related to packet size.
I send a "Hello World" Payload to my remote broker and it is received on the remote broker.
I send a large data set of integers as the payload and the message is not received.
My data that is in the payload is 0.196608 Megabytes in size.
Does the MQTT Client used by node-red have some limiting factor?

It could be the remote broker.

Try sending similar size payload to another remote or even a local broker as a test.

That was my first thought too!
The remote broker has a limit of 0.256MB.
Broker Documentation

That's why I'm now questioning the Node-Red side of things.

That's a bit odd. Is it cloud based? The limit is normally around 250MB not 256KB

Have you tried a local mosquito install?

@knolleary Nick is there a limit to the size of an MQTT packet?
Is there a limit to the size of msg.payload?
Are they documented anywhere?

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I used mqttfx to test it.
I verified Losant's payload size limit by uploading a dummy 256kb json file.
MOCK_DATA_3.json (255.5 KB)
Anything over this size breaks the communication.

I am really just stuck trying to figure out if there is a limiting factor on the node red side.
Does the built-in node-red MQTT-node use Mosquitto as the client?
If so I suppose I can try that too.

I'm not aware of the Mqtt client we use imposing any restrictions other than those the protocol specifies.

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I've sent you test data to my broker and back again and it seems to have worked fine

Also tested it out using and that was fine as well


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