grid.yaml

version: "3"
 
networks:
  main:
    driver: overlay
services:
  hub:
    image: selenium/hub:3.2.0
    ports:
      - "4444:4444"
    networks:
      - main
    deploy:
      mode: replicated
      replicas: 1
      labels:
        selenium.grid.type: "hub"
        selenium.grid.hub: "true"
      restart_policy:
        condition: none
      placement:
        constraints: [node.role == manager]
  chrome:
    image: selenium/node-chrome-debug
    entrypoint: >
      bash -c '
        export IP_ADDRESS=$$(ip addr show eth0 | grep "inet\b" | awk '"'"'{print $$2}'"'"' | awk -F/ '"'"'{print $$1}'"'"' | head -1) &&
        SE_OPTS="-host $$IP_ADDRESS" /opt/bin/entry_point.sh'
    volumes:
      - /dev/urandom:/dev/random
      - /dev/shm:/dev/shm
    environment:
      HUB_PORT_4444_TCP_ADDR: hub
      HUB_PORT_4444_TCP_PORT: 4444
      NODE_MAX_SESSION: 1
    networks:
      - main
    deploy:
      mode: replicated
      replicas: 2
      labels:
        selenium.grid.type: "node"
        selenium.grid.node: "true"
        selenium.grid.node.type: "chrome"
      restart_policy:
        condition: none
      placement:
        constraints: [node.role == manager]
  firefox:
    image: selenium/node-firefox
    entrypoint: >
      bash -c '
        export IP_ADDRESS=$$HOSTNAME &&
        SE_OPTS="-host $$IP_ADDRESS" /opt/bin/entry_point.sh'
    volumes:
      - /dev/shm:/dev/shm
      - /dev/urandom:/dev/random
    environment:
      HUB_PORT_4444_TCP_ADDR: hub
      HUB_PORT_4444_TCP_PORT: 4444
      NODE_MAX_SESSION: 1
    networks:
      - main
    depends_on:
      - hub
    deploy:
      mode: replicated
      replicas: 5
      labels:
        selenium.grid.type: "node"
        selenium.grid.node: "true"
        selenium.grid.node.type: "firefox"
      restart_policy:
        condition: none
      placement:
        constraints: [node.role == manager]
  firefoxBuddy:
    image: selenium/node-firefox
    entrypoint: >
      bash -c '
        export IP_ADDRESS=$$HOSTNAME &&
        SE_OPTS="-host $$IP_ADDRESS" /opt/bin/entry_point.sh'
    volumes:
      - /dev/shm:/dev/shm
      - /dev/urandom:/dev/random
    environment:
      HUB_PORT_4444_TCP_ADDR: hub
      HUB_PORT_4444_TCP_PORT: 4444
      NODE_MAX_SESSION: 1
    networks:
      - main
    depends_on:
      - hub
    deploy:
      mode: replicated
      replicas: 4
      labels:
        selenium.grid.type: "node"
        selenium.grid.node: "true"
        selenium.grid.node.type: "wefirefox"
      restart_policy:
        condition: none
      placement:
        constraints: [node.role == worker]

ip addr show eth0 | grep "inet\b" | awk '"'"'{print $$2}'"'"' | awk -F/ '"'"'{print $$1}'"'"' | head -1
the above command doesn't result in IP

why you have created chrome a Manger we can also create as worker too, what is firefox buddy ?

1. You are creating 2 replicas of chrome(container) and 4 replicas(container) of firefox instance am i right ??

2. What does this attribute do NODE_MAX_SESSION: 1 what i understand this will create only one chrome instance i am right ??