Ansible varialbes

1.什么是变量?

以一个固定的字符串,表示一个不固定的值    version:  1.12

2.定义变量?

2.1.在playbook中定义变量?

    #vars  关键字

[root@manager project1]# cat f2.yml
- hosts: webservers
  vars:
    - file_name: playbook_vars

  tasks:
    - name: Create New File
      file:
        path: /tmp/{{ file_name }}
        state: touch

#vars_file   属于一种共享的方式

[root@manager project1]# cat vars_file.yml
web_packages: httpd
ftp_packages: vsftpd

[root@manager project1]# cat f2.yml
- hosts: webservers
  vars:
    - file_name: playbook_vars

 #调用共享vars_file文件,只不过刚好文件名叫vars_file
  vars_files: ./vars_file.yml

  tasks:
    - name: Create New File
      file:
        path: /tmp/{{ file_name }}
        state: touch

    - name: Installed Packages {{ web_packages }}
      yum:
        name: "{{ web_packages }}"
        state: present

2.在inventory主机清单中定义变量?

2.1：清单文件中直接定义 hosts文件定义--

[webservers]
172.16.1.7
172.16.1.8
[webservers:vars]
file_name=hostsfile_group_vars

2.2：创建hosts_vars group_vars 目录

[root@manager project1]# mkdir hosts_vars   #单个主机
[root@manager project1]# mkdir group_vars   #主机组


#1.单个主机定义和使用方式 (host_vars能分别对不同的主机定义变量)
[root@manager project1]# cat host_vars/172.16.1.7
host_vars_name: 172.16.1.7

[root@manager project1]# cat host_vars/172.16.1.8
host_vars_name: 172.16.1.8

[root@manager project1]# cat f4.yml
- hosts: webservers

  tasks:
    - name: Create New File
      file:
        path: /opt/{{ host_vars_name }}
        state: touch

#2.针对主机组定义的方式
#给指定的webserver组设定变量.其他组主机无法使用该变量
[root@manager project1]# cat group_vars/webservers
group_host_vars: webservers

[root@manager project1]# cat f5.yml
- hosts: webservers
  tasks:
    - name: Create New File {{ group_host_vars }}
      file:
        path:  /opt/{{ group_host_vars }}
        state: touch


#3.针对主机组定义的方式  (给所有的主机和主机组设定变量)
[root@manager project1]# cat group_vars/all
group_host_vars: all

[root@manager project1]# cat f5.yml
- hosts: webservers
  tasks:
    - name: Create New File {{ group_host_vars }}
      file:
        path:  /opt/{{ group_host_vars }}
        state: touch

2.3.通过外置传参定义变量? -e

[root@manager project1]# ansible-playbook -i hosts f6.yml  -e "web_vars=123"

3.变量冲突,优先级?

6.定义相同的变量不同的值，来测试变量的优先级。操作步骤如下   file_name:
  1）在plabook中定义vars变量
  2）在playbook中定义vars_files变量
  3）在inventory主机定义变量
  4）在inventory主机组定义变量
  5）在host_vars中定义变量
  6）在group_vars中定义变量  组      all组
  7）通过执行命令传递变量
 
 
优先级测试:
外置传入参数优先级最高 ---> playbook ( vars_files(共享)--->vars(私有) )
---> host_vars  --> group_vars/group_name ---> group_vars/all

4.变量注册?

[root@manager project1]# cat f8.yml
- hosts: webservers
  tasks:
        # System_Status=$(netstat -lntp)
    - name: Get Network Status
      shell: netstat -lntp | grep "nginx"
      register: System_Status

        # echo "$System_Status"
    - name: Debug output Variables
      debug:
        msg: "{{ System_Status.stdout_lines }}"

5.facts变量?

#1.根据主机的cpu信息,生成不同的配置.
    A: 1核心    work_process 1;
    B: 2核心    work_process 2;

#2.根据主机名称设定不同配置文件
    zabbix_agent
        Server:   ===> 指向172.16.1.61
        Hostname:      web01   web02

[root@manager project1]# cat ./file/zabbix_agent.conf.j2
Server={{ zabbix_server_ip }}
ServerActive={{ zabbix_server_ip }}
Hostname={{ ansible_hostname }}

[root@manager project1]# cat f11.yml
- hosts: webservers
  vars:
    - zabbix_server_ip: 172.16.1.61
  tasks:
    - name: Configure zabbix-agent.conf
      template:
        src: ./file/zabbix_agent.conf.j2
        dest: /tmp/zabbix-agent.conf


#3.根据主机的内存生成不同的配置文件,memcached
[root@manager project1]# cat f12.yml
- hosts: webservers
  tasks:
    - name: Installed Memcached Server
      yum:
        name: memcached
        state: present

    - name: Configure Memcached Server
      template:
        src: ./file/memcached.j2
        dest: /etc/sysconfig/memcached
      notify: Restart Memcached Server

    - name: System Memcached Server
      systemd:
        name: memcached
        state: started
        enabled: yes

  handlers:
    - name: Restart Memcached Server
      systemd:
        name: memcached
        state: restarted

[root@manager project1]# cat file/memcached.j2
PORT="11211"
USER="memcached"
MAXCONN="1024"
CACHESIZE="{{ ansible_memtotal_mb //2 }}"
OPTIONS=""


1.根据cpu
2.根据内存
3.根据主机名
4.Redis配置文件     bind本地地址
5.操作系统不统一

        变量可以进行运算  + - * //




#1.定义变量
    playbook
        vars            私有
        vars_files      共享
    inventory
        host_vars
        group_vars
            group_vars/group_name
            group_vars/all
    外置传参
        -e
#2.测试优先级
    在不改变playbook变量的情况下,使用新的值测试.

#3.变量注册register
    1.将任务执行的结果存储至特定的变量中
    2.可以使用debug模块将变量进行打印输出

    python: 字典
    json 格式化数据
    {
        k1: v1
        k2: v2
    }
#4.facts 

[root@manager project1]# cat f13.yml
- hosts: webservers
  tasks:
    - name: RANDOM
      shell:  echo "$RANDOM"
      register: System_SJ

    - name: Debug
      debug:
        msg: "web_{{ System_SJ.stdout }}"

#1.提取facts变量中的IP地址   mac地址  UUID 等等  只要唯一
    ansible_default_ipv4.address
[root@manager project1]# cat f14.yml
- hosts: webservers
  tasks:

    - name: Debug
      debug:
        msg: "web_{{ ansible_default_ipv4.address }}"

Ansible 流程控制

5.判断语句

1.centos和ubuntu系统都需要安装httpd,  判断系统.
2.安装软件仓库,只有web组的安装webtatic其他的主机全部跳过.
3.TASK任务, TASK1任务执行成功,才会执行TASK2

#根据不同的系统,安装不同的服务
- hosts: webservers
  tasks:
    - name: CentOS Installed Httpd Server
      yum:
        name: httpd
        state: present
      when: ( ansible_distribution == "CentOS" )

    - name: Ubuntu Installed Httpd Server
      yum:
        name: httpd2
        state: present
      when: ( ansible_distribution == "Ubuntu" )

[root@manager project1]# cat f16.yml
- hosts: all
  tasks:
  - name: Add Nginx Yum Repository
    yum_repository:
      name: nginx
      description: Nginx Repository
      baseurl: http://nginx.org/packages/centos/7/$basearch/
    when: ( ansible_hostname is match ("web*"))


[root@manager project1]# cat f17.yml
- hosts: webservers
  tasks:

    - name: Check Httpd Server
      command: systemctl is-active httpd
      register: Check_Httpd
      ignore_errors: yes

    #判断Check_Httpd.rc是否等于0,如果为0则执行任务,否则不执行
    - name: Restart Httpd Server
      systemd:
        name: httpd
        state: restarted
      when: ( Check_Httpd.rc == 0 )

6.循环语句

#一次启动多个服务
[root@manager project1]# cat f18.yml
- hosts: webservers
  tasks:
    - name: Systemd Nginx Status
      systemd:
        name: "{{ item }}"    #调用的变量也不变,也是固定
        state: started

    #固定的语法格式
      with_items:
        - nginx
        - php-fpm


#一次拷贝多个文件
[root@manager project1]# cat f19.yml
- hosts: webservers
  tasks:
    - name: Configure nginx.conf
      copy:
        src: '{{ item.src }}'
        dest: '{{ item.dest }}'
        mode: '{{ item.mode }}'
      with_items:
        - { src: ./file/nginx.conf.j2, dest: /etc/nginx/nginx.conf, mode: '0644' }
        - { src: ./file/kold.oldxu.com.conf.j2, dest: /etc/nginx/conf.d/kold.oldxu.com.conf, mode: '0600' }



#创建多个用户,一次创建多个? 3个用户  TASK
[root@manager project1]# cat f20.yml
- hosts: webservers
  tasks:
    - name: Create User
      user:
        name: "{{ item }}"

      with_items:
        - test1
        - test2
        - test3
        - test4


#1.创建tt1 --> bin  tt2 -->root tt3 --->adm   附加组
[root@manager project1]# cat  f20.yml
- hosts: webservers
  tasks:
    - name: Create User
      user:
        name: "{{ item.name }}"
        groups: "{{ item.groups }}"

      with_items:
        - { name: tt1, groups: bin }
        - { name: tt2, groups: root }
        - { name: tt3, groups: adm }



1.标准循环                   --->居多
    item
    with_items:
       - test
2.字典循环:                   --->居多
    itme.name
    with_items:
        - { name: test }


3.变量循环
- hosts: webservers
  tasks:
    - name: ensure a list of packages installed
      yum: name={{ packages }} state=present
      vars:
        packages:
          - httpd
          - httpd-tools

7.handlers

[root@manager project1]# cat f22.yml
- hosts: webservers
  tasks:

    - name: Installed Nginx and PHP Packages
      yum:
        name: nginx
        state: present

    - name: Configure nginx.conf
      template:
        src: ./file/nginx.conf.j2
        dest: /etc/nginx/nginx.conf
      #监控-->changed状态-->通知-->handlers--->name-->Restart Nginx Server
      notify: Restart Nginx Server
      #notify:
      #  - Restart Nginx Server
      #  - Restart php Server

    - name: Systemd Nginx Server
      systemd:
        name: nginx
        state: started
        enabled: yes

#当nginx或php配置文件发生变更才会触发此操作
  handlers:
    - name: Restart Nginx Server
      systemd:
        name: nginx
        state: restarted


#3.handlers注意事项
    1.无论多少个task通知了相同的handlers，handlers仅会在所有tasks结束后运行一次。
    2.只有task发生改变了才会通知handlers，没有改变则不会触发handlers.
    3.不能使用handlers替代tasks、因为handlers是一个特殊的tasks。

变量->facts-->判断-->循环

    - 1.安装Rsyncd服务  (循环)
    - 2.安装Redis   (bind  本地IP地址)    facts
    - 3.安装NFS      (配置文件,创建目录,客户端挂载)    变量