# TCP Node - message splitting question
**URL:** https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573
**Category:** General
**Created:** [31 January 2022 23:47 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573 "2022-01-31T23:47:23Z")
**Posts on this page:** 12
**Page:** 1
### Author:  [@hazymat](https://discourse.nodered.org/u/hazymat)
#### Post date: [31 January 2022 23:47 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/1 "2022-01-31T23:47:23Z")
I am sending 40,002 byte TCP packet from a microcontroller and reading it into Node-RED from the TCP node.
I'm reading the contents of the buffer using the debug node.
1. The TCP packet seems to end up as two messages in Node-RED. Here you can see the sizes:
Is there any rhyme or reason as to why they are split or in what proportion?
1. Is there a good way to detect disconnections? If I reset the microcontroller, it seems to show in the node status that one connection exists. Then when I restart the MCU it sometimes sees two connections, and sometimes seems to disconnect the first one. Any ideas why that may be?
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [1 February 2022 00:49 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/2 "2022-02-01T00:49:34Z")
From Google -
Ethernet traffic moves in units called frames. The maximum size of frames is called the Maximum Transmission Unit (MTU). When a network device gets a frame that is larger than its MTU, the data is either fragmented into smaller frames, or dropped. ... An Ethernet packet larger than 1500 bytes is called a **jumbo frame**.
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### Author:  [@hazymat](https://discourse.nodered.org/u/hazymat)
#### Post date: [1 February 2022 00:52 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/3 "2022-02-01T00:52:34Z")
> [@Sean-McG](#):
>
> larger than 1500 bytes
Thanks, but how does this explain the message segmentation shown above?
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [1 February 2022 00:57 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/4 "2022-02-01T00:57:28Z")
Fair point, does it always split at the same sizes ?
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### Author:  [@hazymat](https://discourse.nodered.org/u/hazymat)
#### Post date: [1 February 2022 01:01 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/5 "2022-02-01T01:01:12Z")
It does seem to split into the same buffer sizes, when the same number of bytes are sent.
However if I send different numbers of bytes in the first place, the message splitting can be different.
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [1 February 2022 01:17 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/6 "2022-02-01T01:17:30Z")
I guess you can join the two payload together, but as to why it splits as it does I'm not sure.
Maybe there is a setting in NR that needs tweaking ?
You will need to wait for the smart people to help out 😉
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### Author:  [@dceejay](https://discourse.nodered.org/u/dceejay)
#### Post date: [1 February 2022 10:27 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/7 "2022-02-01T10:27:09Z")
How do you have the tcp in node configured ? Which version of Node-RED ? Which OS are you running on ?
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### Author:  [@hazymat](https://discourse.nodered.org/u/hazymat)
#### Post date: [1 February 2022 10:44 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/8 "2022-02-01T10:44:20Z")
Hi, it's:
**OS** : Ubuntu 20.04.2 LTS
**NodeRED version** : 2.0.4
Here is how I have configured the TCP node:
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [1 February 2022 17:35 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/9 "2022-02-01T17:35:39Z")
Have you tried output single buffer ?
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [5 February 2022 02:18 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/10 "2022-02-05T02:18:33Z")
@hazymat Did you get anywhere with this ?
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### Author:  [@hazymat](https://discourse.nodered.org/u/hazymat)
#### Post date: [6 February 2022 11:57 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/11 "2022-02-06T11:57:20Z")
I tried setting output to single buffer, but it doesn't return anything. (Client connects okay, but no packets are shown on debug output)...
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [7 April 2022 11:57 UTC](https://discourse.nodered.org/t/tcp-node-message-splitting-question/57573/12 "2022-04-07T11:57:30Z")
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