Ansible常用指令

动机

记录一下常用的Ansible指令、模块，方便检索。

Ansible主机

/etc/ansible/hosts中，server是目标服务器列表名，包含两个服务器

[spark]
10.0.0.1
10.0.0.2

Ansible Shell模块

# 在spark集群上执行ls指令
$ ansible spark -m shell -a "ls"

Ansible-playbook

执行较大的复杂任务时，以YAML的声明语法来配置，并且可以放置一些模板类文件和资源文件等。

.
|___python.yml
|___python.host
|___roles
| |___python
| | |___defaults  # 默认变量
| | |___handlers  # 可以被任务使用或者任何该任务之外的地方
| | |___files
| | |___vars      # 其它变量
| | |___templates # 模板
| | |___meta      # 元数据
| | |___tasks     # 主要任务列表
| | | |___main.yml
| |___airflow
| | |___tasks
| | | |___main.yml
| | | |___templates
| | | | |___airflow.cfg

变量

---
# 声明变量
foo:
  field1: one
  field2: two

# 使用base_path
- hosts: app_servers
  vars:
      app_path: { { base_path } }/22

# 在命令行传入变量
$ ansible-playbook release.yml --extra-vars "hosts=vipers user=starbuck"

# 文件形式
$ ansible-playbook release.yml --extra-vars "@some_file.json"

更多的变量还有3类作用域等，以后用到再加。

文件

# 将files目录下的conf/发送到目标节点
- name: copy conf files
  copy: src=conf/agent.conf dest=/opt/flume/apache-flume-1.7.0-bin/conf/

handler

# handlers/main.yml
---

- name: start telegraf
  service: name=telegraf state=started

# 拷贝docker配置文件并触发docker重启
- name: copy docker conf to dest host
  copy: src=conf/docker.conf dest=/etc/telegraf/telegraf.d/
  when: "'docker' in group_names"
  notify: restart telegraf

任务

roles目录就是按具体安装的功能模块划分，比如python模块、jdk模块、spark模块等等，他们相互不重复，并且可以有依赖关系，比如jdk -> spark，通过多个role的组合搭配出各种环境的配置方法。

# python/tasks/main.yml

- name: Install pip
  apt: 
    name: python-pip
    state: present
  become: false

- name: Upgrade pip
  pip:
    name: pip
    extra_args: --upgrade -i https://pypi.doubanio.com/simple/
  become: false

# airflow/tasks/main.yml

- name: Create virtualenv for airflow
  command: virtualenv /home/ubuntu/airflow_v creates=/home/ubuntu/airflow_v
  become: false

- name: Install mysqlclient
  apt:
    name: libmysqlclient-dev
    state: present
  become: true

- name: Install airflow within `airflow_v`
  pip:
    name: apache-airflow[all]
    extra_args: -i https://pypi.doubanio.com/simple/
    virtualenv: /home/ubuntu/airflow_v

- name: Install celery[redis] within `airflow_v`
  pip:
    name: celery[redis]
    extra_args: -i https://pypi.doubanio.com/simple/
    virtualenv: /home/ubuntu/airflow_v
    
- name: Create Airflow home
  file:
    path: /home/ubuntu/airflow
    state: directory
    mode: 0755

- name: Initialize airflow database
  command: source /home/ubuntu/airflow_v/bin/activate && /home/ubuntu/airflow_v/bin/airflow initdb creates=/home/ubuntu/airflow/airflow.cfg
  environment:
    AIRFLOW_HOME: /home/ubuntu/airflow
    
- name: Syncronize airflow configuration
  synchronize:
    src: templates/airflow.cfg
    dest: /home/ubuntu/airflow/airflow.cfg
  become: false

入口文件

python.yml是ansible入口文件，包含目标host、运行的具体任务。

---
# 发布机上的代码初始化
- hosts: spark
  roles:
    - python
    - airflow

下面是任务中常用的模块

---

apt安装模块

# 安装pip
- name: Install pip
  apt: 
    name: python-pip
    state: present
  become: false

Pip安装模块

# 使用pip升级pip
- name: Upgrade pip
  pip:
  name: pip
  extra_args: --upgrade -i https://pypi.doubanio.com/simple/
  become: false
  
# 使用指定虚拟环境安装依赖
- name: Install celery[redis] within `airflow_v`
  pip:
    name: celery[redis]
    extra_args: -i https://pypi.doubanio.com/simple/
    virtualenv: /home/ubuntu/airflow_v

Shell模块

- name: Initialize airflow database
  command: source /home/ubuntu/airflow_v/bin/activate && /home/ubuntu/airflow_v/bin/airflow initdb creates=/home/ubuntu/airflow/airflow.cfg
  environment:
    AIRFLOW_HOME: /home/ubuntu/airflow

File模块

# 在目标服务器上创建权限为0755的目录
- name: Create Airflow home
  file:
    path: /home/ubuntu/airflow
    state: directory
    mode: 0755

Synchronize模块

# 将本地文件同步到目标服务器上
- name: Syncronize airflow configuration
  synchronize:
    src: templates/airflow.cfg
    dest: /home/ubuntu/airflow/airflow.cfg
  become: false

下载模块

# 从指定URL下载文件到目标服务器指定目录
- name: Download the Go tarball
  get_url:
    url: "{{ go_download_location }}"
    dest: /usr/local/src/{{ go_tarball }}
    checksum: "{{ go_tarball_checksum }}"

Systemd模块

# 重启docker服务
- name: restart docker
  systemd:
    state: restarted
    daemon_reload: yes
    name: docker
  become: true

Template模块

# 将templates目录下的docker.my模板复制到目标服务器的/etc/default/docker目录
- name: Configure docker mirror registry to Aliyun
  template: src=docker.my dest=/etc/default/docker
  notify: restart docker
  become: true

Blockinfile模块

# 一个官网例子，在/etc/hosts里添加映射
- name: Add mappings to /etc/hosts
  blockinfile:
    path: /etc/hosts
    block: |
      {{ item.ip }} {{ item.name }}
    marker: "# {mark} ANSIBLE MANAGED BLOCK {{ item.name }}"
  with_items:
    - { name: host1, ip: 10.10.1.10 }
    - { name: host2, ip: 10.10.1.11 }
    - { name: host3, ip: 10.10.1.12 }

Copy模块

# 拷贝zookeeper配置文件
- name: copy zookeeper conf to dest host
  copy: src=conf/zookeeper.conf dest=/etc/zookeeper/conf/

Service模块

- name: restart telegraf
  service: name=telegraf state=restarted

引用

1. http://docs.ansible.com/ansible/latest/
2. 华尔街见闻