ModbusTCP RTU over TCP

[piton4ik]

hello,
I read my energy meters TENSE EM-07K using a custom python script with a library (from pyModbusTCP.client import ModbusClient) that returns a json array to zabbix, is there a standard functionality in the system to poll these counters with standard solutions?

[troffasky]

I do something similar, ish. Python script connects to RS485 adaptor, fetches parameters [also sends to MQTT], this is then piped in to zabbix_sender -> Zabbix server.
But I just googled this and it looks like this is already part of Zabbix agent2!

https://www.zabbix.com/integrations/modbus

[piton4ik]

I do something similar, ish. Python script connects to RS485 adaptor, fetches parameters [also sends to MQTT], this is then piped in to zabbix_sender -> Zabbix server.
But I just googled this and it looks like this is already part of Zabbix agent2!
https://www.zabbix.com/integrations/modbus

I know about this feature
here is a list of keys for Mudbus GET
https://www.zabbix.com/documentation/current/en/manual/appendix/items/modbus
but there is an RTU key only for SERIAL connection (rtu://COM1:9600:8n, rtu://ttyS0:9600, ascii://ttyS1)
I need to read Modbus RTU over TCP(rtu://192.168.1.224:502) i use rs485->Ethernet convertors

I now have a ready test bench with meter, rs485 convertors and zabbix test system,
I can help with testing new feature functionality, it would be great to implement new functionality

[troffasky]

It's a shame that the "example" items are not actually usable, they are just fragments of what you would put in an item.
Anyway.
I think one of us is confused here. I think that RTU and TCP are mutually exclusive - either one or the other is used, not both. Your post implies that you think you want to use RTU over TCP, but I don't think that's a thing.

[piton4ik]

It's a shame that the "example" items are not actually usable, they are just fragments of what you would put in an item.
Anyway.
I think one of us is confused here. I think that RTU and TCP are mutually exclusive - either one or the other is used, not both. Your post implies that you think you want to use RTU over TCP, but I don't think that's a thing.

ok,
let's try to test, maybe I made a mistake somewhere in the configuration of the item key,


item key: modbus.get[endpoint,<slave id>,<function>,<address>,<count>,<type>,<endiannes s>,<offset>]

legend:
endpoint - tcp://192.168.1.145:511(fixed on router)
slave id - 1
function - 3
address - 500
count - 5
type - uint16
endianness - le
offset - 0

modbus.get[tcp://192.168.6.145:511,1,3,500,5,uint16,le,0]
modbus.get[tcp://192.168.6.145:511,<1>,<3>,<500>,<5>,<uint16>,<le>,<0>]

when I try to save this key the system gives an error, explain where I am wrong

[cyber]

definitely do not use <>-s there... those are just for marking keywords...

But I tried to enter one item and I got errors in any way and combination I tried... leaving out most of them, relying on defaults etc. etc..
Exact same as you on v7 and a bit longer text on v6...
: incorrect syntax near "". [items.php:690 → CApiWrapper->__call() → CFrontendApiWrapper->callMethod() → CApiWrapper->callMethod() → CFrontendApiWrapper->callClientMethod() → CLocalApiClient->callMethod() → CItem->create() → CItemGeneral->checkInput() → CApiService::exception() in include/classes/api/services/CItemGeneral.php:492]

[troffasky]

Two things you can try:
- test with zabbix_get
- Use "Named sessions", which are mentioned on Modbus integration page, but not mentioned on modbus.get page

From here:

https://support.zabbix.com/browse/ZBX-25442

Example item:
modbus.get[tcp://10.6.4.51:502,1,4,13958,3,uint32,mle,0]
I tried adding this item on my Zabbix, server accepts it [I do not have any Modbus TCP equipment].

[piton4ik]

I inserted your key into a new Item and saved it, everything is fine,
then I edited it to my real ip and other parameters, all it works, thank you

[cyber]

I think it is somekind of encoding issue... When I pasted both now to notepad++ and let it show "all characters"... this is what is shown..The one provided by troffasky worked OK for me also...