If you need to read multiple (variable number) of sensors into Cacti, the following python script will read the sensors and format the output ready for Cacti. Be aware though that the sensor numbering is based on their serial numbers - the order will change if sensors with different serial numbers are added or removed!!! #!/usr/bin/env python from os import path, listdir, system from time import sleep # Borrowing some elements from https://github.com/timofurrer/w1thermsensor/blob/master/w1thermsensor/core.py THERM_SENSOR_DS18S20 = 0x10 THERM_SENSOR_DS1822 = 0x22 THERM_SENSOR_DS18B20 = 0x28 RESOLVE_TYPE_STR = {"10": THERM_SENSOR_DS18S20, "22": THERM_SENSOR_DS1822, "28": THERM_SENSOR_DS18B20} BASE_DIRECTORY = "/sys/bus/w1/devices" SLAVE_FILE = "w1_slave" # function to find how many sensors are connected, works for 3 types of sensor def get_available_sensors(): types = [THERM_SENSOR_DS18S20, THERM_SENSOR_DS1822, THERM_SENSOR_DS18B20] is_sensor = lambda s: any(s.startswith(hex(x)[2:]) for x in types) return [(RESOLVE_TYPE_STR[s[:2]], s[3:]) for s in listdir(BASE_DIRECTORY) if is_sensor(s)] # function to return the initial 2 letters of the device ID ("28" for DS18B20 sensors) def slave_prefix(mytype): return "%s-" % hex(mytype)[2:] # function that grabs the raw temperature data from a sensor, requires full path+filename def read_temp_raw(device_file): f_1 = open(device_file, 'r') raw_reading = f_1.readlines() f_1.close() return raw_reading # function that checks that the reading of a sensor was good and strips out the temperature def read_temp(device_file): lines = read_temp_raw(device_file) while lines[0].strip()[-3:] != 'YES': time.sleep(0.2) lines = read_temp_raw(device_file) equals_pos = lines[1].find('t=') temp = float(lines[1][equals_pos+2:])/1000 return temp n = 0 for sensor in get_available_sensors(): n = n +1 sp = slave_prefix(sensor[0]) sensorpath = path.join(BASE_DIRECTORY, sp + sensor[1], SLAVE_FILE) print('T'+str(n)+':'+str(read_temp(sensorpath))),
Output from multiple DS18B20 to Cacti
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