Question 121942 in Redis Question posted in
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Redis – How to set up airflow worker to allow webserver fetch logs on different machine with docker?

I just recently installed airflow 2.1.4 with docker containers, I’ve successfully set up the postgres, redis, scheduler, 2x local workers, and flower on the same machine with docker-compose.

Now I want to expand, and set up workers on other machines.

I was able to get the workers up and running, flower is able to find the worker node, the worker is receiving tasks from the scheduler correctly, but regardless of the result status of the task, the task would be marked as failed with error message like below:

*** Log file does not exist: /opt/airflow/logs/test/test/2021-10-29T14:38:37.669734+00:00/1.log
*** Fetching from: http://b7a0154e7e20:8793/log/test/test/2021-10-29T14:38:37.669734+00:00/1.log
*** Failed to fetch log file from worker. [Errno -3] Temporary failure in name resolution

Then I tried replaced AIRFLOW__CORE__HOSTNAME_CALLABLE: 'socket.getfqdn' with AIRFLOW__CORE__HOSTNAME_CALLABLE: 'airflow.utils.net.get_host_ip_address'

I got this error instead:

*** Log file does not exist: /opt/airflow/logs/test/test/2021-10-28T15:47:59.625675+00:00/1.log
*** Fetching from: http://172.18.0.2:8793/log/test/test/2021-10-28T15:47:59.625675+00:00/1.log
*** Failed to fetch log file from worker. [Errno 113] No route to host

Then I tried map the port 8793 of the worker with its host machine (in worker_4 below), now it’s returning:

*** Failed to fetch log file from worker. [Errno 111] Connection refused

but sometimes still give "Temporary failure in name resolution" error.

I’ve also tried to copy the URL in the error, and change replace the IP with the host machine ip, and got this message:

Forbidden
You don't have the permission to access the requested resource. It is either read-protected or not readable by the server.

Please let me know if additional info is needed.

Thanks in advance!

Below is my docker-compose.yml for the scheduler/webserver/flower:

version: '3.4'

x-hosts: &extra_hosts
  postgres: XX.X.XX.XXX
  redis: XX.X.XX.XXX

x-airflow-common:
  &airflow-common
  image: ${AIRFLOW_IMAGE_NAME:-apache/airflow:2.1.4}
  environment:
    &airflow-common-env
    AIRFLOW__CORE__EXECUTOR: CeleryExecutor
    AIRFLOW__CORE__SQL_ALCHEMY_CONN: postgresql+psycopg2://airflow:airflow@postgres/airflow
    AIRFLOW__CELERY__RESULT_BACKEND: db+postgresql://airflow:airflow@postgres/airflow
    AIRFLOW__CELERY__BROKER_URL: redis://:@redis:6379/0
    AIRFLOW__CORE__FERNET_KEY: ''
    AIRFLOW__CORE__DAGS_ARE_PAUSED_AT_CREATION: 'true'
    AIRFLOW__CORE__LOAD_EXAMPLES: 'false'
    AIRFLOW__CORE__DEFAULT_TIMEZONE: 'America/New_York'
    AIRFLOW__CORE__HOSTNAME_CALLABLE: 'airflow.utils.net.get_host_ip_address'
    AIRFLOW_WEBSERVER_DEFAULT_UI_TIMEZONE: 'America/New_York'
    AIRFLOW__API__AUTH_BACKEND: 'airflow.api.auth.backend.basic_auth'
    _PIP_ADDITIONAL_REQUIREMENTS: ${_PIP_ADDITIONAL_REQUIREMENTS:- apache-airflow-providers-slack}
  volumes:
    - ./dags:/opt/airflow/dags
    - ./logs:/opt/airflow/logs
    - ./plugins:/opt/airflow/plugins
    - ./assets:/opt/airflow/assets
    - ./airflow.cfg:/opt/airflow/airflow.cfg
    - /etc/hostname:/etc/hostname
  user: "${AIRFLOW_UID:-50000}:${AIRFLOW_GID:-0}"
  extra_hosts: *extra_hosts


services:
  postgres:
    container_name: 'airflow-postgres'
    image: postgres:13
    environment:
      POSTGRES_USER: airflow
      POSTGRES_PASSWORD: airflow
      POSTGRES_DB: airflow
    volumes:
      - ./data/postgres:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD", "pg_isready", "-U", "airflow"]
      interval: 5s
      retries: 5
    restart: always
    ports:
      - '5432:5432'

  redis:
    image: redis:latest
    container_name: 'airflow-redis'
    expose:
      - 6379
    healthcheck:
      test: ["CMD", "redis-cli", "ping"]
      interval: 5s
      timeout: 30s
      retries: 50
    restart: always
    ports:
      - '6379:6379'
    

  airflow-webserver:
    <<: *airflow-common
    container_name: 'airflow-webserver'
    command: webserver
    ports:
      - 8080:8080
    healthcheck:
      test: ["CMD", "curl", "--fail", "http://localhost:8080/health"]
      interval: 10s
      timeout: 10s
      retries: 5
    restart: always
    depends_on:
      - redis
      - postgres

  airflow-scheduler:
    <<: *airflow-common
    container_name: 'airflow-scheduler'
    command: scheduler
    healthcheck:
      test: ["CMD-SHELL", 'airflow jobs check --job-type SchedulerJob --hostname "$${HOSTNAME}"']
      interval: 10s
      timeout: 10s
      retries: 5
    restart: always
    depends_on:
      - redis
      - postgres

  airflow-worker1:
    build: ./worker_config
    container_name: 'airflow-worker_1'
    command: celery worker -H worker_1
    healthcheck:
      test:
      - "CMD-SHELL"
      - 'celery --app airflow.executors.celery_executor.app inspect ping -d "celery@$${HOSTNAME}"'
      interval: 10s
      timeout: 10s
      retries: 5
    environment:
      <<: *airflow-common-env
      DUMB_INIT_SETSID: "0"
    restart: always
    depends_on:
      - redis
      - postgres
    volumes: 
      - ./dags:/opt/airflow/dags
      - ./logs:/opt/airflow/logs
      - ./plugins:/opt/airflow/plugins
      - ./assets:/opt/airflow/assets
      - ./airflow.cfg:/opt/airflow/airflow.cfg
    extra_hosts: *extra_hosts

  airflow-worker2:
    build: ./worker_config
    container_name: 'airflow-worker_2'
    command: celery worker -H worker_2
    healthcheck:
      test:
      - "CMD-SHELL"
      - 'celery --app airflow.executors.celery_executor.app inspect ping -d "celery@$${HOSTNAME}"'
      interval: 10s
      timeout: 10s
      retries: 5
    environment:
      <<: *airflow-common-env
      DUMB_INIT_SETSID: "0"
    restart: always
    depends_on:
      - redis
      - postgres
    volumes: 
      - ./dags:/opt/airflow/dags
      - ./logs:/opt/airflow/logs
      - ./plugins:/opt/airflow/plugins
      - ./assets:/opt/airflow/assets
      - ./airflow.cfg:/opt/airflow/airflow.cfg
    extra_hosts: *extra_hosts

  flower:
    <<: *airflow-common
    container_name: 'airflow_flower'
    command: celery flower
    ports:
      - 5555:5555
    healthcheck:
      test: ["CMD", "curl", "--fail", "http://localhost:5555/"]
      interval: 10s
      timeout: 10s
      retries: 5
    restart: always
    depends_on:
      - redis
      - postgres

and my docker-compose.yml for worker on another machine:

version: '3.4'

x-hosts: &extra_hosts
  postgres: XX.X.XX.XXX
  redis: XX.X.XX.XXX

x-airflow-common:
  &airflow-common
  environment:
    &airflow-common-env
    AIRFLOW__CORE__EXECUTOR: CeleryExecutor
    AIRFLOW__CORE__SQL_ALCHEMY_CONN: postgresql+psycopg2://airflow:airflow@postgres/airflow
    AIRFLOW__CELERY__RESULT_BACKEND: db+postgresql://airflow:airflow@postgres/airflow
    AIRFLOW__CELERY__BROKER_URL: redis://:@redis:6379/0
    AIRFLOW__CORE__FERNET_KEY: ''
    AIRFLOW__CORE__DAGS_ARE_PAUSED_AT_CREATION: 'true'
    AIRFLOW__CORE__LOAD_EXAMPLES: 'false'
    AIRFLOW__CORE__DEFAULT_TIMEZONE: 'America/New_York'
    AIRFLOW__CORE__HOSTNAME_CALLABLE: 'airflow.utils.net.get_host_ip_address'
    AIRFLOW_WEBSERVER_DEFAULT_UI_TIMEZONE: 'America/New_York'
    AIRFLOW__API__AUTH_BACKEND: 'airflow.api.auth.backend.basic_auth'
  volumes:
    - ./dags:/opt/airflow/dags
    - ./logs:/opt/airflow/logs
    - ./plugins:/opt/airflow/plugins
    - ./assets:/opt/airflow/assets
    - ./airflow.cfg:/opt/airflow/airflow.cfg
    - /etc/hostname:/etc/hostname
  user: "${AIRFLOW_UID:-50000}:${AIRFLOW_GID:-0}"
  extra_hosts: *extra_hosts

services:
  worker_3:
    build: ./worker_config
    restart: always
    extra_hosts: *extra_hosts
    volumes:
      - ./airflow.cfg:/opt/airflow/airflow.cfg
      - ./dags:/opt/airflow/dags
      - ./assets:/opt/airflow/assets
      - ./logs:/opt/airflow/logs
      - /etc/hostname:/etc/hostname
    entrypoint: airflow celery worker -H worker_3
    environment:
      <<: *airflow-common-env
      WORKER_NAME: worker_147
    healthcheck:
      test: ['CMD-SHELL', '[ -f /usr/local/airflow/airflow-worker.pid ]']
      interval: 30s
      timeout: 30s
      retries: 3

  worker_4:
    build: ./worker_config_py2
    restart: always
    extra_hosts: *extra_hosts
    volumes:
      - ./airflow.cfg:/opt/airflow/airflow.cfg
      - ./dags:/opt/airflow/dags
      - ./assets:/opt/airflow/assets
      - ./logs:/opt/airflow/logs
      - /etc/hostname:/etc/hostname
    entrypoint: airflow celery worker -H worker_4_py2 -q py2
    environment:
      <<: *airflow-common-env
      WORKER_NAME: worker_4_py2
    healthcheck:
      test: ['CMD-SHELL', '[ -f /usr/local/airflow/airflow-worker.pid ]']
      interval: 30s
      timeout: 30s
      retries: 3
    ports:
      - 8793:8793
Tags:

2

Answers


  1. 0

    For this issue: " Failed to fetch log file from worker. [Errno -3] Temporary failure in name resolution"

    Looks like the worker’s hostname is not being correctly resolved. The web program of the master needs to go to the worker to fetch the log and display it on the front-end page. This process is to find the host name of the worker. Obviously, the host name cannot be found, Therefore, add the host name to IP mapping on the master’s vim /etc/hosts

    1. You need to have the image that’s going to be used in all your containers except message broker, meta database and worker monitor. Following is the Dockerfile.

    2.If using LocalExecutor, the scheduler and the webserver must be on the same host.

    Docker file:

    FROM puckel/docker-airflow:1.10.9
COPY airflow/airflow.cfg ${AIRFLOW_HOME}/airflow.cfg
COPY requirements.txt /requirements.txt
RUN pip install -r /requirements.txt

    here is for deps for docker to deploy for webserver

    webserver:

    The web program of the master needs to go to the worker to fetch the log and display it on the front-end page. This process is to find the host name of the worker. Obviously, the host name cannot be found, therefore, add the host name to IP mapping on the master's vim /etc/hosts

    to fix it:

    Fist of all, get configuration file by typing:

    helm show values apache-airflow/airflow > values.yaml

    After that check that fixPermissions is true.

    You need to enable persistence volumes:
    Enable persistent volumes
    enabled: true
    Volume size for worker StatefulSet
    size: 10Gi
    If using a custom storageClass, pass name ref to all statefulSets here
    storageClassName:
    Execute init container to chown log directory.

    fixPermissions: true

    Update your installation by:

    helm upgrade --install airflow apache-airflow/airflow -n ai
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  2. 0

    Your scheduler does not expose the 8793 port. Try to expose it in docker-compose.yml file.

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