ansible 脚手架-3-使用 playbook 做个导演

playbook和运行方法

shell脚本一般以.sh结尾，保存了常用的命令，可以多次运行，ansible也有类似的脚本，用的是YAML格式，起了个名字叫playbook。

运行方式:
ansible-playbook deploy.yml

用playbook部署apache

新建文件： deploy.yml

手动部署步骤：

1. 安装apache包
2. 拷贝httpd的配置文件，之后重启apache
3. 拷贝默认的测试页面 index.html
4. 启动apache服务

跟随手动部署的步骤，我们可以写playbook了，就好像导演安排演员演戏一样。

首先普及几个playbook的关键字，放心，很少，很简单。

• hosts: 主机ip，或主机组名，或关键字all
• remote_user：用户名，用来执行脚本
• vars：变量
• tasks：分派任务，定义一些列动作来执行playbook。每个动作叫做action，调用一个模块
  • action语法：
    • module:key=value
  • 常用模块：
    • yum
    • copy
    • template
    • ...
• handers: 是playbook中的event，默认不执行。在action里触发才执行，并只执行一次，多次触发无效。

show me the code：

---
- hosts: web
  vars:
    http_port: 80
    max_clients: 200
  remote_user: root
  tasks:
  - name: ensure apache is at the latest version
    yum: pkg=httpd state=latest

  - name: Write the configuration file
    template: src=templates/httpd.conf.j2 dest=/etc/httpd/conf/httpd.conf
    notify:
    - restart apache

  - name: Write the default index.html file
    template: src=templates/index.html.j2 dest=/var/www/html/index.html

  - name: ensure apache is running
    service: name=httpd state=started
  handlers:
    - name: restart apache
      service: name=httpd state=restarted

---

测试运行记录：

[root@master ~/ansible-note]# vim deploy_apache.yml # 写入上面的yml内容
[root@master ~/ansible-note]# mkdir templates
[root@master ~/ansible-note]# cd templates/
[root@master ~/ansible-note/templates]# echo "hello ansible">index.html.j2   # 创建html模板
[root@master ~/ansible-note/templates]# ll
total 4
-rw-r--r-- 1 root root 14 Dec 28 19:03 index.html.j2
[root@master ~/ansible-note/templates]# mv httpd.conf httpd.conf.j2
[root@master ~/ansible-note/templates]# vim httpd.conf.j2  # 修改默认配置
    
    1003 <VirtualHost *:80>
    1004 #    ServerAdmin webmaster@dummy-host.example.com
    1005     DocumentRoot /var/www/html
    1006     ServerName ansible.howie.wang
    1007 #    ErrorLog logs/dummy-host.example.com-error_log
    1008 #    CustomLog logs/dummy-host.example.com-access_log common
    1009 </VirtualHost>


[root@master ~/ansible-note/templates]# cd ..
[root@master ~/ansible-note]# ansible-playbook deploy_apache.yml 

PLAY [test] ********************************************************************

TASK [setup] *******************************************************************
ok: [10.129.204.250]

TASK [ensure apache is at the latest version] **********************************
changed: [10.129.204.250]

TASK [write the configuration file] ********************************************
changed: [10.129.204.250]

TASK [write the default index.html file] ***************************************
changed: [10.129.204.250]

TASK [ensure apache is running] ************************************************
fatal: [10.129.204.250]: FAILED! => {"changed": false, "failed": true, "msg": "httpd: apr_sockaddr_info_get() failed for client1\nhttpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for ServerName\n(98)Address already in use: make_sock: could not bind to address [::]:80\n(98)Address already in use: make_sock: could not bind to address 0.0.0.0:80\nno listening sockets available, shutting down\nUnable to open logs\n"}

# 这里出错了，因为原机器占用80端口在运行nginx，下面去把nginx停一下。

RUNNING HANDLER [restart apache] ***********************************************
    to retry, use: --limit @/root/ansible-note/deploy_apache.retry

PLAY RECAP *********************************************************************
10.129.204.250             : ok=4    changed=3    unreachable=0    failed=1   

[root@master ~/ansible-note]# ansible test -a "service nginx stop"
10.129.204.250 | SUCCESS | rc=0 >>
Stopping nginx daemon: nginx
Stop nginx success.

[root@master ~/ansible-note]# ansible-playbook deploy_apache.yml 

PLAY [test] ********************************************************************

TASK [setup] *******************************************************************
ok: [10.129.204.250]

TASK [ensure apache is at the latest version] **********************************
ok: [10.129.204.250]

TASK [write the configuration file] ********************************************
ok: [10.129.204.250]

TASK [write the default index.html file] ***************************************
ok: [10.129.204.250]

TASK [ensure apache is running] ************************************************
changed: [10.129.204.250]

PLAY RECAP *********************************************************************
10.129.204.250             : ok=5    changed=1    unreachable=0    failed=0   

添加10.129.204.250 ansible.howie.wang到本地的hosts文件
打开浏览器，访问ansible.howie.wang

你会看到刚才写进html的内容：

hello ansible

成功！

最后，听说还有个网站能进行json和yaml的互转，简直不能再强大了！

提供json和yml互转的在线网站： http://www.json2yaml.com/

参考

https://ansible-book.gitbooks.io/ansible-first-book/content/ansibleyong_jiao_ben_guan_li_zhu_ji.html