A script to expose a locally attached UPS via SNMP

nut_ups_mib.py

#!/usr/bin/env python3

import sys
import subprocess

DEBUG_LOG_FILE = "/tmp/nut_ups_mib.log"

debug_logging = False  # Set to True to enable debug logging

def debug_log(message):
    if not debug_logging:
        return
    try:
        with open(DEBUG_LOG_FILE, "a") as log_file:
            log_file.write(message + "\n")
    except Exception:
        pass

# Overwrite the debug log at startup if logging is enabled.
#if debug_logging:
#    with open(DEBUG_LOG_FILE, "w") as f:
#        f.write("Debug log initialized.\n")
debug_log("Script started with arguments: " + " ".join(sys.argv))

# Mapping from UPS MIB OIDs (as defined in RFC 1628) to a tuple:
# (NUT key, conversion function, SNMP type)
# This is for an Eaton 5E 1200 G2
mapping = {
    # Identification group
    '.1.3.6.1.2.1.33.1.1.1.0': ('ups.mfr', lambda x: x, "string"),             # Manufacturer
    '.1.3.6.1.2.1.33.1.1.2.0': ('ups.model', lambda x: x, "string"),             # Model
    '.1.3.6.1.2.1.33.1.1.3.0': ('ups.serial', lambda x: x, "string"),            # Serial number
    '.1.3.6.1.2.1.33.1.1.4.0': ('ups.firmware', lambda x: x, "string"),          # Firmware revision

    # Battery group
    '.1.3.6.1.2.1.33.1.2.1.0': ('battery.charge', lambda x: int(x), "integer"),   # Battery status (here using charge %)
    '.1.3.6.1.2.1.33.1.2.3.0': ('battery.runtime', lambda x: int(x)/60, "integer"),  # Battery time remaining
    '.1.3.6.1.2.1.33.1.2.4.0': ('battery.voltage', lambda x: float(x), "gauge"),  # Battery voltage
    '.1.3.6.1.2.1.33.1.2.5.0': ('battery.current', lambda x: float(x), "gauge"),  # Battery current
    '.1.3.6.1.2.1.33.1.2.6.0': ('battery.temperature', lambda x: float(x), "gauge"),  # Battery temperature
    '.1.3.6.1.2.1.33.1.2.7.0': ('battery.type', lambda x: x, "string"),           # Battery chemistry/type

    # Input group
    '.1.3.6.1.2.1.33.1.3.2.0': ('input.frequency', lambda x: int(float(x)), "integer"),  # Input line frequency
    '.1.3.6.1.2.1.33.1.4.1.0': ('input.voltage', lambda x: int(float(x)), "integer"),    # Input line voltage

    # Output group
    '.1.3.6.1.2.1.33.1.4.2.0': ('output.voltage', lambda x: int(float(x)), "integer"),   # Output voltage
    '.1.3.6.1.2.1.33.1.4.3.0': ('output.frequency', lambda x: int(float(x)), "integer"),   # Output frequency

    # Load group
    '.1.3.6.1.2.1.33.1.5.2.0': ('ups.load', lambda x: int(x), "integer"),          # Load (%)

    # Bypass group
    '.1.3.6.1.2.1.33.1.6.3.8': ('bypass.voltage', lambda x: int(float(x)), "integer"),  # Bypass voltage

    # Alarm group – these mappings use placeholder NUT keys.
    '.1.3.6.1.2.1.33.1.7.1.0': ('alarm.battery', lambda x: x, "string"),           # Alarm: Battery Bad
    '.1.3.6.1.2.1.33.1.7.3.0': ('outlet.1.status', lambda x: x, "string"),         # Alarm: Outlet status (e.g. off)
    '.1.3.6.1.2.1.33.1.8.2.0': ('alarm.output.overload', lambda x: x, "string"),     # Alarm: Output Overload
    '.1.3.6.1.2.1.33.1.8.3.0': ('alarm.bypass.active', lambda x: x, "string"),       # Alarm: Bypass Active
    '.1.3.6.1.2.1.33.1.8.4.0': ('alarm.shutdown', lambda x: x, "string"),            # Alarm: Shutdown
    '.1.3.6.1.2.1.33.1.8.5.0': ('alarm.replace.battery', lambda x: x, "string"),     # Alarm: Replace Battery

    '.1.3.6.1.2.1.33.1.9.1.0': ('alarm.test.result', lambda x: x, "string"),         # Alarm: Test Result
    '.1.3.6.1.2.1.33.1.9.2.0': ('alarm.low.battery', lambda x: x, "string"),         # Alarm: Low Battery
    '.1.3.6.1.2.1.33.1.9.3.0': ('alarm.overload', lambda x: x, "string"),            # Alarm: Overload
    '.1.3.6.1.2.1.33.1.9.4.0': ('alarm.overtemp', lambda x: x, "string"),            # Alarm: Over Temperature
    '.1.3.6.1.2.1.33.1.9.5.0': ('alarm.shutdown.delay', lambda x: x, "string"),      # Alarm: Shutdown Delay
    '.1.3.6.1.2.1.33.1.9.6.0': ('alarm.start.delay', lambda x: x, "string"),         # Alarm: Start Delay
    '.1.3.6.1.2.1.33.1.9.7.0': ('alarm.comm.lost', lambda x: x, "string"),           # Alarm: Communication Lost
    '.1.3.6.1.2.1.33.1.9.8.0': ('alarm.fuse', lambda x: x, "string"),                # Alarm: Fuse
    '.1.3.6.1.2.1.33.1.9.9.0': ('alarm.charger.fault', lambda x: x, "string"),       # Alarm: Charger Fault
    '.1.3.6.1.2.1.33.1.9.10.0': ('alarm.charger.overload', lambda x: x, "string")    # Alarm: Charger Overload
}

def get_nut_values():
    try:
        debug_log("Calling upsc to get UPS values.")
        output = subprocess.check_output(['/usr/bin/upsc', 'eaton'],
                                         universal_newlines=True,
                                         stderr=subprocess.STDOUT)
        debug_log("upsc output:\n" + output)
    except Exception as e:
        debug_log("upsc call failed: " + str(e))
        return {}
    values = {}
    for line in output.splitlines():
        if "Init SSL without certificate database" in line:
            debug_log("Skipping SSL init line: " + line)
            continue
        if ':' in line:
            key, value = line.split(':', 1)
            values[key.strip()] = value.strip()
    debug_log("Parsed UPS values: " + str(values))
    return values

def main():
    # Always ignore the first argument (-g) and use the second as the requested OID.
    if len(sys.argv) < 3:
        debug_log("Insufficient arguments provided.")
        sys.exit(1)
    requested_oid = sys.argv[2]
    debug_log("Requested OID: " + requested_oid)

    if requested_oid in mapping:
        nut_key, conv, snmp_type = mapping[requested_oid]
        debug_log("Mapping found: " + requested_oid + " -> " + nut_key)
        nut_values = get_nut_values()
        if nut_key in nut_values:
            try:
                value = conv(nut_values[nut_key])
                debug_log("Converted value: " + str(value))
                # Output exactly three lines: OID, SNMP type, and the value.
                print(requested_oid)
                print(snmp_type)
                print(value)
            except Exception as e:
                debug_log("Conversion error for " + nut_key + ": " + str(e))
                print("NONE")
        else:
            debug_log("NUT key not found in UPS output: " + nut_key)
            print("NONE")
    else:
        debug_log("Requested OID not in mapping: " + requested_oid)
        print("NONE")

if __name__ == '__main__':
    main()

couple this with

rocommunity ups
pass .1.3.6.1.2.1.33 /etc/snmp/nut_ups_mib.py

supports only snmpget not snmpwalk e.g.

snmpget -v2c -c ups localhost .1.3.6.1.2.1.33.1.1.2.0
SNMPv2-SMI::mib-2.33.1.1.2.0 = STRING: "Eaton 5E 1200 G2"

The Synology SNMP UPS implementation asks for these OIDs

.1.3.6.1.2.1.33.1.1.2.0
.1.3.6.1.2.1.33.1.7.1.0
.1.3.6.1.2.1.33.1.8.2.0
.1.3.6.1.2.1.33.1.8.3.0
.1.3.6.1.2.1.33.1.9.8.0
.1.3.6.1.2.1.33.1.1.1.0
.1.3.6.1.2.1.33.1.1.2.0
.1.3.6.1.2.1.33.1.1.3.0
.1.3.6.1.2.1.33.1.1.4.0
.1.3.6.1.2.1.33.1.2.1.0
.1.3.6.1.2.1.33.1.2.3.0
.1.3.6.1.2.1.33.1.2.4.0
.1.3.6.1.2.1.33.1.2.5.0
.1.3.6.1.2.1.33.1.2.6.0
.1.3.6.1.2.1.33.1.2.7.0
.1.3.6.1.2.1.33.1.3.2.0
.1.3.6.1.2.1.33.1.4.1.0
.1.3.6.1.2.1.33.1.4.2.0
.1.3.6.1.2.1.33.1.4.3.0
.1.3.6.1.2.1.33.1.5.2.0
.1.3.6.1.2.1.33.1.6.3.8
.1.3.6.1.2.1.33.1.7.1.0
.1.3.6.1.2.1.33.1.7.3.0
.1.3.6.1.2.1.33.1.8.2.0
.1.3.6.1.2.1.33.1.8.3.0
.1.3.6.1.2.1.33.1.8.4.0
.1.3.6.1.2.1.33.1.8.5.0
.1.3.6.1.2.1.33.1.9.1.0
.1.3.6.1.2.1.33.1.9.2.0
.1.3.6.1.2.1.33.1.9.3.0
.1.3.6.1.2.1.33.1.9.4.0
.1.3.6.1.2.1.33.1.9.5.0
.1.3.6.1.2.1.33.1.9.6.0
.1.3.6.1.2.1.33.1.9.7.0
.1.3.6.1.2.1.33.1.9.8.0
.1.3.6.1.2.1.33.1.9.9.0
.1.3.6.1.2.1.33.1.9.10.0