ansible playbook用法

playbook做爲ansible重要的企業實戰解決方案。如下是個人aliyun ansible學習筆記。

playbook 基本使用

建立playbook文件

touch playbooktest.yml
vim playbooktest.yml

編寫playbook

---
- hosts: websrvs
  remote_user: root

  task: 
    - name: hello
      command: hostname

執行playbook
ansible-playbook playbooktest.yml

palybook構成

palybook採用YAML語言編寫，有多個劇本組成，每一個劇本由若干個task組成，每一個task調用不一樣的模塊，最終在目標機器上執行。ansible playbook至關於linux shell腳本。
yaml.org 查看更多的語法詳情

playbook之Hosts

第一種編寫方式

---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: create new file
      file: name=/data/newfile state=touch
    - name: create a new user
      user: name=test2 system=yes
    - name: insall package
      yum: name=httpd
    - name: copy files
      copy: src=/var/www/html/index.html

第二種編寫方式

---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: create new file
      file: 
        name: /data/newfile
        state: touch

    - name: create a new user
      user:
        name: test2
        system: yes

    - name: insall package
      yum: 
        name:httpd
    
    - name: copy files
      copy:
        src:/var/www/html/index.html

只進行檢查，不真正執行
ansible-playbook test.yml --check
ansible-playbook -C test.yml

handlers和notify結合使用條件觸發

• handlers至關於一個觸發器，配合notify使用。

---
- hosts: websrvs
  remote_user: root

  tasks:
     - name: install httpd
       yum: name=httpd
       tags: installed

     - name: config file
       copy: src=files/httpd.conf dest=/etc/httpd/conf/ backup=yes
       notify: 
        - restart service
        - check the nginx process
    
     - name: restart httpd
       service: name=httpd state=start enableed=yes
       tags: rshttpd

  handlers:
    - name: restart service
      service: name=httpd state=restarted
    - name: check the nginx process
      shell: killall -0 nginix> /tmp/nginx.log

ansible tags的使用

添加tags後，能夠經過tags調用，經過指定標籤執行特定task.
ansible-playbook -t installed,rshttpd httpd.yml

playbook中變量的使用

ansible變量只能數字字母下劃線組成，且只能字母開頭，包括系統變量和自定義變量。

• 查詢某個關鍵字的系統變量。

ansible websrvs -m setup -a 'filter=ansible_fqdn'

• 引用外部的變量

---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: create new file
      file: 
        name: /data/newfile
        state: touch

    - name: create a new user
      user:
        name: test2
        system: yes

    - name: insall package
      yum: 
        name: {{ pkname }}

執行playbook並經過-e傳入變量
ansbible-playbook app.yml -e 'pkname=httpd pkname2=vbss'

• 在playbook中定義變量

---
- hosts: websrvs
  remote_user: root
  vars:
    - pkname1: httpd
    - pkname2: vbs
     
  tasks:
    - name: create new file
      file: 
        name: /data/newfile
        state: touch

    - name: insall package
      yum: 
        name: {{ pkname }}

執行playbook自動引用內部定義的變量
ansbible-playbook app.yml

• 在ansible的hosts文件中定義變量，

/etc/ansible/hosts

[webserver]
192.168.1.2 http_port=81
192.168.1.4 http_port=82

playbook引用hosts中的變量

---
- hosts: websrvs
  remote_user: root
  vars:
    - pkname1: httpd
    - pkname2: vbs
  
  tasks:
    - name: set hostname
      hostname: name=wwww.{{http_port}}.baidu.com