# Modbus server not running on linux

**URL:** <https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695>\
**Category:** General\
**Created:** [20 February 2024 11:12 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695 "2024-02-20T11:12:45Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![PRABHAKAR82](https://avatars.discourse-cdn.com/v4/letter/p/e47c2d/32.png) [@PRABHAKAR82](https://discourse.nodered.org/u/PRABHAKAR82)\
**Post date:** [20 February 2024 11:12 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/1 "2024-02-20T11:12:46Z")

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![modbus](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/5/d5037f60f1095d8c6b6045ac618ce8cdbf0cdee3.png)  
 ![modbus1](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/0/70bf1cea9e385dcfeb1941e945cb87036dad14d4.png)  
I configure Modbus server, but this error is coming "Error: listen EACCES: permission denied 192.168.0.114:502". node-red is running on Linux ubuntu(Orange pi-pc).

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**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [20 February 2024 12:10 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/2 "2024-02-20T12:10:06Z")

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> [@PRABHAKAR82](#):
>
> EACCES

Read up this error and access to ports below 1000 on linux

the account running node-red needs permission to open ports below 1000

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**Author:** ![PRABHAKAR82](https://avatars.discourse-cdn.com/v4/letter/p/e47c2d/32.png) [@PRABHAKAR82](https://discourse.nodered.org/u/PRABHAKAR82)\
**Post date:** [20 February 2024 12:24 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/3 "2024-02-20T12:24:06Z")

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> [@Steve-Mcl](#):
>
> 000

If I use port:1025 then this error is coming--"Is Not A Valid Memory Write Message To Server"

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**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [20 February 2024 13:13 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/4 "2024-02-20T13:13:35Z")

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Is the modbus server running on the same device as node-red? Because if it is, you should probably be using localhost (AKA 127.0.0.1) as the address?

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**Author:** ![PRABHAKAR82](https://avatars.discourse-cdn.com/v4/letter/p/e47c2d/32.png) [@PRABHAKAR82](https://discourse.nodered.org/u/PRABHAKAR82)\
**Post date:** [20 February 2024 13:17 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/5 "2024-02-20T13:17:17Z")

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yes Modbus server running on same device and I am using 192.168.0.114

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**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [20 February 2024 13:30 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/6 "2024-02-20T13:30:09Z")

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When using one service to connect to another on the same server, you should use the internal address and not the external one as you have done.

If you use the external address, the traffic has to loop out via the network card and back in again and then do the opposite on the way back. Along the way, it will hit any edge security you have enabled which may be the reason your connection was being rejected.

So try using `localhost` or `127.0.0.1` as the address instead.

One other thought though - you aren't using Docker are you?

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**Author:** ![PRABHAKAR82](https://avatars.discourse-cdn.com/v4/letter/p/e47c2d/32.png) [@PRABHAKAR82](https://discourse.nodered.org/u/PRABHAKAR82)\
**Post date:** [21 February 2024 04:45 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/7 "2024-02-21T04:45:27Z")

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Thanks for your response. I connect to Modbus server from another device in the same network.  
But as you see in picture modbus server not running it gives error.

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [21 May 2024 04:46 UTC](https://discourse.nodered.org/t/modbus-server-not-running-on-linux/85695/8 "2024-05-21T04:46:14Z")

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