edgexfoundry / device-snmp

Main Author: Anantha Boyapalle

Copyright 2016-17, Dell, Inc.

SNMP Micro Service - device service for connecting SNMP devices to EdgeX.

device-snmp's Issues

Where to change or fix the source port of SNMP microservice packet?

I got a strange problem. When I fellow the EdgeX document '5.3. SNMP - Adding a Device to EdgeX' to add my SNMP device. I couldn't get any data from my SNMP device. Originally, I thought it was because no one was listening to the response packet of SNMP agent. But it seems like there is another reason. Someone knows why the source port of SNMP microservice packet is arbitrary value, and how the SNMP microservice to listen this packet. Thanks a lot.

Tracking process:
(1) Use a command 'sudo docker logs -f edgex-device-snmp' to get information. the key information as bellow

[2018-11-28 01:51:30.959] boot - 8  INFO [Thread-190] --- SNMPDriver: ProcessCommand: get, interface: HTTP, address: 172.16.12.29, attributes: OID:1.3.6.1.4.1.10297.100.2.1.1.0:community:public, value: 1
[2018-11-28 01:51:36.961] boot - 8 ERROR [Thread-190] --- SNMPDriver: Exception in getValue():org.edgexfoundry.exception.DeviceNotFoundException: could not find device 'Connection timed out'.

(2) Use Wireshark to check the packet. There are request and response packets. But the soource port of request packet is 58477

(3) Check listening ports with a command 'netstat'. No one cares about it.
$ netstat -l

(4) Download and trace the source code 'device-snmp' on the github edgexfoundry. There is no 58477.

(5) Modify the file 'docker-compose.yml' to add port listen on edgex-device-snmp and run 'docker-compose up -d device-snmp' to restart the container. Everything works fine now.

  device-snmp:
    image: edgexfoundry/docker-device-snmp:0.6.0
    ports:
      - "49989:49989"
      - "58477:58477"
    container_name: edgex-device-snmp
    hostname: edgex-device-snmp
    networks:
      - edgex-network
    volumes:
      - db-data:/data/db
      - log-data:/edgex/logs
      - consul-config:/consul/config
      - consul-data:/consul/data
    depends_on:
      - data
      - command

(6) The strangest thing is that I remove it later, and restart the SNMP container. It still works fine. And I restart the SNMP container everytime, the source port of packet will change to another number.