Monitoring Liebert DS Crac

C

Thread Starter

cfgriffith

Hi All.

I am having some difficulty (mainly do to lack of knowledge of modbus) in monitoring some a Liebert DS CRAC via modbus.

In documentation these are the things I want to monitor:

Index, Register(Num), Data Label, Unit, Scale, Access
36, 30100(1), System Operating State, , x1, RO
37, 30102(1), System Status, , x1, RO
54, 30130(1), Return Humidity, % RH, x10, RO
90, 30279(1), System Status, , x1, RO
203, 30743(1), Return Air Temperature, deg F, x10, RO
204, 30744(1), Supply Air Temperature, deg F, x10, RO
205, 30745(1), Supply Air Temperature Set Point, deg F, x10, RO
380, 10025(1), Fan State
381, 10026(1), Cooling State
390, 10037(1), Compressor High Head Pressure (Compressors->Compressor [1])
391, 10038(1), Compressor Low Suction Pressure (Compressors->Compressor [1])
392, 10039(1), Compressor Thermal Overload (Compressors->Compressor [1])
393, 10040(1), Compressor Pump Down Issue (Compressors->Compressor [1])
394, 10041(1), Compressor High Head Pressure (Compressors->Compressor [2])
395, 10042(1), Compressor Low Suction Pressure (Compressors->Compressor [2])
396, 10043(1), Compressor Thermal Overload (Compressors->Compressor [2])
397, 10044(1), Compressor Pump Down Issue (Compressors->Compressor [2])
469, 10232(1), Unit Off
470, 10233(1), Unit On
471, 10234(1), Unit Partial Shutdown
472, 10235(1), Unit Shutdown
473, 10236(1), High Power Shutdown
474, 10237(1), Unit Standby

I have successfully installed, and have a wrapper for, check_modbus for a monitoring software called Nagios. However I am unsure how to use the above information in the modbus check command. It looks like I need an 'address' but I don't have anything called an "address" in the above fields. When I try to use the registers as the address it comes up with invalid address.

Command flags:

usage check_modbus.sh [-H hostnameip] [-d device] [-F format] (register)[-a address] [-f function] [-l lower limit] [-u upper limit]

check_modbus -H 10.4.2.14 -F 7 -f 4 -a 10233
Read failed: Illegal data address

Is there some number somewhere I need to get that I am missing? Thanks in advanced.
 
Hi.

The address is not important for MODBUS/TCP devices. Try to specify 01. Also you may find this address in the device settings.

> Is there some number somewhere I need to get that I am missing?
 
C
I found out how the registers work. So anything starting with 30 is actually function type 4 and anything starting with 10 is format type 2. Going from there I have gotten some of the checks to work.

I.E. : 30279(1), System Status, , x1, RO is function 4 device 279

Problem is I am getting most of the analog checks to work, but having problems with the multi-state values.
 
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