Quick reference

Maintained by: Michael Oberdorf IT-Consulting

Source code: GitHub

Container image: DockerHub

Supported tags and respective Dockerfile links

• latest, 1.1.2
• 1.1.1
• 1.0.4
• 1.0.3
• 1.0.2
• 1.0.1
• 1.0.0

Summary

The container image is based on Alpine Linux with python3 interpreter. The tool is written in python and connects to a MQTT server. After that, it loops over the configured SNMP endpoints and graps the configured OIDs. The collected SNMP data will be transformed as a json object and published to the given MQTT topic.

Configuration

Container configuration

The container reads some configuration via environment variables.

Environment variable name	Description	Required	Default value
CONFIG_FILE	The configuration file that contains the connection parameters to MQTT and the SNMP endpoints.	OPTIONAL	/app/etc/snmp2mqtt.json

Configuration file

The path and filename to the general configuration file can be set via environment variable CONFIG_FILE. By default, the script will use /app/etc/snmp2mqtt.json.

Inside this file we need to configure the MQTT server connection parameters and the SNMP endpoint connection parameters.

Example

{
  "DEBUG": true,
  "devices": [
    "EXAMPLE"
  ],
  "mqtt": {
    "client_id": "snmp2mqtt",
    "user": "snmp2mqtt",
    "password": "myMQTTPassword",
    "server": "test.mosquitto.org",
    "port": 1883,
    "tls": false,
    "retain": true,
    "hostname_validation": false,
    "protocol_version": 3
    },
  "EXAMPLE": {
    "server": "127.0.0.1",
    "port": 161,
    "snmpCredentials": {
      "user": "snmpUser",
      "password": "snmpPassword",
      "algorithm": "MD5"
    },
    "snmpEncryption": {
      "password": "snmpEncryptionKey",
      "algorithm": "DES"
    },
    "snmpOID2Attribute": {
      "1.3.6.1.4.1.2021.4.3.0": "memTotalSwap"
    },
    "mqttTopic": "de/oberdorf-itc/devices/EXAMPLE"
  }
}

Field description

Field	Type	Description
DEBUG	Boolean	Enable debug output on stdout
devices	Array	A List of names that represent SNMP endpoints. These keywords are later used inside the configuation file.
mqtt	Object	Contains MQTT specific configuration parameters.
mqtt.client_id	String	The MQTT client identifier.
mqtt.user	String	The username to authenticate to the MQTT server.
mqtt.password	String	The password to authenticate to the MQTT server.
mqtt.server	String	IP address or FQDN of the MQTT server.
mqtt.port	String	The TCP port number of the MQTT server.
mqtt.tls	Boolean	If a TLS encrpted communication should be established or not.
mqtt.hostname_validation	Boolean	Validate the hostname from the servercertificate or not.
mqtt.protocol_version	Integer	The MQTT protocol version. Can be 3 (for MQTTv311) or 5 (for MQTTv5).
<device>	Object	Contains the SNMP endpoint specific configuration parametes.
<device>.server	String	IP address or FQDN of the SNMP endpoint.
<device>.port	Integer	The TCP port number of the SNMP endpoint.
<device>.snmpCredentials	Object	The SNMP endpoint credentials for authentication.
<device>.snmpCredentials.user	String	The username to authenticate to the SNMP endpoint.
<device>.snmpCredentials.password	String	The password to authenticate to the SNMP endpoint.
<device>.snmpCredentials.algorithm	String	The algorithm to use when authenticating to the SNMP endpoint (supported: MD5, SHA, SHA224, SHA256, SHA384, SHA512).
<device>.snmpEncryption	Object	The SNMP endpoint data encrption parameters.
<device>.snmpEncryption.password	String	The SNMP data encrption password.
<device>.snmpEncryption.algorithm	String	The SNMP data encrption algorithm (supported: DES, 3DES, AES128, AES192, AES256).
<device>.snmpOID2Attribute	Object	List of SNMP OIDs and a human readable name.
<device>.snmpOID2Attribute.<OID>	String	A human readable translation of the given OID.
<device>.mqttTopic	String	the MQTT topic to publish the colected device data.

Running the container image

docker run --rm -v ./myConfig.json:/app/etc/snmp2mqtt.json:ro oitc/snmp2mqtt:latest

Docker compose configuration

services:
  snmp2mqtt:
    container_name: snmp2mqtt
    image: oitc/snmp2mqtt:1.0.0
    restart: "no"
    user: 3917:3917
    volumes:
      - /srv/docker/snmp2mqtt/etc/snmp2mqtt.json:/app/etc/snmp2mqtt.json:ro

Donate

I would appreciate a small donation to support the further development of my open source projects.

License

Copyright (c) 2023-2025 Michael Oberdorf IT-Consulting

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.