Elasitcsearch cluster with docker swarm

[8e6d5b4d49f69e9edb4c (이소라)]

Hi, all.
I tried to run Elasticsearch cluster with docker swarm.
However, there is a problem described in https://github.com/elastic/elasticsearch-docker/issues/91#issuecomment-319679786.
Solutions from above issue are:

• To specify the network interface. Set network.host: _eth0_ instead of network.host: 0.0.0.0 in elasticsearch.yml
• Or not to use VIP (Virtual IP) mode. Set endpoint_mode: dnsrr in docker-compose.yml

I want to know the reason why VIP is a problem.
Why elasticsearch cluster doesn't work when advertising VIP endpoint?

My configuration is:
elasticsearch-master.yml

network.host: 0.0.0.0
cluster.name: docker-test-cluster
node.master: true
node.data: false
node.ingest: false
discovery.zen.ping.unicast.hosts: ["elasticsearch-master"]

elasticsearch-data.yml

network.host: 0.0.0.0
cluster.name: docker-test-cluster
node.master: false
node.data: true
node.ingest: false
discovery.zen.ping.unicast.hosts: ["elasticsearch-master"]

elasticsearch-coordinating-only.yml

network.host: 0.0.0.0
cluster.name: docker-test-cluster
node.master: false
node.data: false
node.ingest: false
discovery.zen.ping.unicast.hosts: ["elasticsearch-master"]

docker-compose.yml is:

version: "3.3"
services:
  elasticsearch-master:
    hostname: elasticsearch-master
    image: docker.elastic.co/elasticsearch/elasticsearch-oss:6.2.3
    configs:
    - source: elasticsearch-master.yml
      target: /usr/share/elasticsearch/config/elasticsearch.yml
      uid: '1000'
      gid: '1000'
      mode: 0444
    networks:
    - backend

  elasticsearch-data:
    hostname: elasticsearch-data
    image: docker.elastic.co/elasticsearch/elasticsearch-oss:6.2.3
    configs:
    - source: elasticsearch-data.yml
      target: /usr/share/elasticsearch/config/elasticsearch.yml
      uid: '1000'
      gid: '1000'
      mode: 0440
    environment:
    - bootstrap.memory_lock=true
    - "ES_JAVA_OPTS=-Xms32g -Xmx32g"
    volumes:
    - /elasticsearch/data:/usr/share/elasticsearch/data
    networks:
    - backend

  elasticsearch-coordinating-only:
    hostname: elasticsearch-coordinating-only
    image: docker.elastic.co/elasticsearch/elasticsearch-oss:6.2.3
    configs:
    - source: elasticsearch-coordinating-only.yml
      target: /usr/share/elasticsearch/config/elasticsearch.yml
      uid: '1000'
      gid: '1000'
      mode: 0440
    environment:
    - bootstrap.memory_lock=true
    - "ES_JAVA_OPTS=-Xms32g -Xmx32g"
    networks:
    - backend
    ports:
    - "9200:9200"