Socket Listener cannot assign address

Telegraf
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1

Hello,

In reality I want to log data from a industrial camera, that publishes data over a tcp-socket, into influxdb. For testing I build a docker container (“dmc”) that simulates the cam…

Now I have docker-compose with three containers:

  1. DMC-“Camera”-Container, that waits for a socket connection on port 9006 to send data
  2. InfluxDB to save the data
  3. Telegraf-Container, that should connect to the dmc container and save data to the influxDB

Here is the docker compose…

services:
  influxdb:
    image: influxdb:2.7.6
    container_name: "influxDB"
    restart: unless-stopped
    ports:
      - "18086:8086"
    expose:
      - 8086
    environment:
      [xxx]
    networks:
      - backend

  telegraf_dmc:
    image: telegraf:1.31.0
    container_name: telegraf_dmc
    environment:
      INFLUX_TOKEN:[...]
    entrypoint: telegraf --config http://influxdb:8086/api/v2/telegrafs/[...]
    depends_on:
      - influxdb
    expose:
      - "9006"
    restart: unless-stopped
    networks:
      - backend

  dmc:
    image: socketmock:dev
    container_name: dmc
    expose:
      - "9006"
    ports:
      - "9006:9006"
    networks:
      - backend

networks:
  backend:

The telegraf config looks like:

[agent]
  [...]

[[outputs.influxdb_v2]]
  urls = ["http://influxdb:8086"]
  token = "$INFLUX_TOKEN"
  organization = [...]
  bucket = "dmc"

[[inputs.socket_listener]]
  service_address = "tcp://dmc:9006"

The result is:

[telegraf] Error running agent: starting input inputs.socket_listener: listen tcp 172.21.0.2:9006: bind: cannot assign requested address

So it resolves the dns correctly (dmc → 172.21.0.2)
When I use my own socket subscriber everything works also fine…
and the influxdb-connection works (with oder inputs) also fine.

Thanks for help…

2

Hi,

bind: cannot assign requested address

This error usually means that something is already established on this port or you don’t have permissions.

Keep in mind that the socket listener is a listener and not a subscriber. It opens up a connection on a port and waits for messages to get passed to it.

3

Hi,

thanks for the clarification! Then I totally misunderstood the plugin. Is there a socket client plugin that can subscribe to a web socket server to meet my requirements like described above?

4

You could use your existing python script and have it pass metrics to telegraf using the execd plugin. For more info see: