GRAYLOG_IS_MASTER Env variable not working about graylog-docker

[joschi]

Tring to set is_master = false for new slave node useing ENV - GRAYLOG_IS_MASTER, however graylog config still have "is_master = true" value.

How exactly are you checking this?

[joschi]

I'm unable to reproduce this with Graylog 2.4.3.

I've been using the following docker-compose.yml file:

version: '2'
services:
  mongo:
    image: mongo:3
  elasticsearch:
    image: docker.elastic.co/elasticsearch/elasticsearch:5.6.6
    environment:
      - http.host=0.0.0.0
      - xpack.security.enabled=false
      - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
    ulimits:
      memlock:
        soft: -1
        hard: -1
    mem_limit: 1g
  # Graylog: https://hub.docker.com/r/graylog/graylog/
  graylog:
    image: graylog/graylog:2.4.3-1
    environment:
      - GRAYLOG_PASSWORD_SECRET=somepasswordpepper
      # Password: admin
      - GRAYLOG_ROOT_PASSWORD_SHA2=8c6976e5b5410415bde908bd4dee15dfb167a9c873fc4bb8a81f6f2ab448a918
      - GRAYLOG_WEB_ENDPOINT_URI=http://127.0.0.1:9000/api
      - GRAYLOG_IS_MASTER=false
    links:
      - mongo
      - elasticsearch
    ports:
      # Graylog web interface and REST API
      - 9000:9000

This is the node information directly from the Graylog REST API:

$ curl -u admin:admin 'http://127.0.0.1:9000/api/system/cluster/node?pretty=true'
{
  "cluster_id" : "00000000-0000-0000-0000-000000000000",
  "node_id" : "6001cd88-9250-41c7-8437-cefd4b6a78d5",
  "type" : "server",
  "transport_address" : "http://172.19.0.4:9000/api/",
  "last_seen" : "2018-01-30T12:45:19.000Z",
  "short_node_id" : "6001cd88",
  "hostname" : "20e868c9a8cf",
  "is_master" : false
}

is_master: false means that this node is not a master node.