Modbus exporter
Prometheus exporter which retrieves stats from a modbus tcp system and exports them via HTTP for Prometheus consumption.
Reproduce diagram
Go to: https://bramp.github.io/js-sequence-diagrams/
Note right of Prometheus: promehteus.yml \n --- \n target: Modbus-TCP-10.0.0.5 \n sub_target: Modbus-Unit-10 \n module: VendorXY
Prometheus->Exporter: http://xxx.de/metrics?target=10.0.0.5&sub_target=10&module=vendorxy
Note right of Exporter: modbus.yml \n --- \n module: VendorXY \n - temperature_a: 400001 \n - temperature_b: 400002
Exporter->Modbus_TCP_10.0.0.5: tcp://10.0.0.5?unit=10®ister=400001
Modbus_TCP_10.0.0.5->Modbus_RTU_10: rtu://_?register=400001
Modbus_RTU_10-->Modbus_TCP_10.0.0.5: value=20
Modbus_TCP_10.0.0.5-->Exporter: value=20
Exporter->Modbus_TCP_10.0.0.5: tcp://10.0.0.5?unit=10®ister=400002
Modbus_TCP_10.0.0.5->Modbus_RTU_10: rtu://_?register=400002
Modbus_RTU_10-->Modbus_TCP_10.0.0.5: value=19
Modbus_TCP_10.0.0.5-->Exporter: value=19
Exporter-->Prometheus:temperature_a{module="VendorXY",sub_target="10"} 20 \ntemperature_b{module="VendorXY",sub_target="10"} 19
Building
make build
Getting Started
The modbus exporter needs to be passed target (including port), module and sub_module as parameters by Prometheus, this can be done with relabelling (see prometheus.yml).
Once Prometheus is properly configured, run the exporter via:
./modbus_exporter [flags]
Supported flags:
Usage of ./modbus_exporter:
-config.file string
Sets the configuration file. (default "modbus.yml")
-modbus-listen-address string
The address to listen on for HTTP requests exposing modbus metrics. (default ":9602")
-telemetry-listen-address string
The address to listen on for HTTP requests exposing telemetry metrics about the exporter itself. (default ":9602")
Visit http://localhost:9602/modbus?target=1.2.3.4:502&module=fake&sub_target=1 where 1.2.3.4:502 is the IP and port number of the modbus IP device to get metrics from, while module and sub_target parameters specify which module and subtarget to use from the config file. If your device doesn't use sub-targets you can usually just set it to 1.
Visit http://localhost:9602/metrics to get the metrics of the exporter itself.
Configuration File
Check out modbus.yml
for more details on the configuration file
format.
TODO
-
Rework logging.
-
Revisit bit parsing.
-
Print name, version, ... on exporter startup.
Misc info
ModBus RTU
Support for serial ModBus (RTU) was dropped in git commit d06573828793094fd2bdf3e7c5d072e7a4fd381b. Please send a PR if you need it again. For now, we suggest using a ModBus PLC/bridge/master to bridge from RTU into TCP.
Software provenance
This is forked from https://github.com/lupoDharkael/modbus_exporter which was not maintained any more and did not follow Prometheus best practices. Initially, development happened in https://github.com/mxinden/modbus_exporter which has now been retired in favour of https://github.com/RichiH/modbus_exporter .