Hello Node-Red community! I have a problem with distinguishing TCP connections. I have multiple devices connected to me using TCP IN node via port XXX. If i send any information using TCP OUT node, all the devices receive that info, while i need to send it only to a specific device. Even if i mov…

Could you post a picture of a network diagram of your setup?

[network] It would be something like this i assume.

If you add debug nodes and set them to complete message object, you will see the _session object received. e.g. {"type":"tcp","id":"4069fb619d89bbf9"} If you do not overwrite this object and make sure it gets to the out node, it should only reply to the incoming tcp connection. You can read abou…

I had already tried assigning the devices to diffrent ports and separate nodes like in the uploaded picture. [message] Injecting messages to port 999 will cause the upper connection (port 998) to receive the message too. I also tried moving them to separate flows, but that also didnt do anything.

I think i have found the mistake that i was making: Injecting a msg directly into TCP Output without any session info resulted in it being sent to every active connection. I have made a crude program that catches msg._session and sends a message using that session information, and it seems to work…

If you post a export example flow, we can then give you some pointers. How to import/export a flow In order to make code readable and usable it is necessary to surround your code with three backticks (also known as a left quote or backquote ```) ``` code goes here ``` You can edit and corre…

No need, i will manage it somehow. Thank you for your time and putting me on the right path.

How to distinguish TCP connections with TCP IN/OUT nodes?

General

E1cid 18 December 2023 09:59 6

Again add a debug to the tcp in node, set to full message object and look at the _session object. The _session object has to make it to the out node. It has nothing to do with port numbers.

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How to distinguish TCP connections with TCP IN/OUT nodes?

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