Modbus TCP proxy would be great

Feature Requests
1

I didn’t find a slim modbus tcp proxy for openwrt yet.
Here modbus devices (RTU & TCP) are scattered from the basement to the roof.
I managed to “convert” the RTU devces to TCP with a RS485-to-USB Adapter and mbusd available as openwrt package.
Because the modbus server usually did not accept request from many tcp clients a proxy is required.
I have found a proxy written in python. But I did not like this solution very much because it requires tons of python packages to be installed.
Maybe its running on openwrt. The usual way is to run it on a separate (virtual) server.
I would prefer a slim solution running on openwrt itself.

Is there anything out there?

2

There is a Rust port https://github.com/tiagocoutinho/modbus-proxy-rs

Maybe it can simply be cross-compiled with https://github.com/goreleaser/example-rust

Depending on your use case you could also look into Modbus connected with ESPHome or Eclipse Kura to your application.

3

@dekarl
Thanks for your hint to the rust port.
But I did not understand what goreleaser is, and how to use.

Finaly I forked mobus-proxy-rs, and added some files to get it build with aarch64.
You can find my version here.
Remember. I never use rust before. Maybe there are tons of errors ….

4

You can use nginx stream module, or firewall dnat {limit is per second, not swarm size)