• Hosts 执行的远程主机列表
  • Tasks 任务集
  • Variables 内置变量或自定义变量在playbook中调用
  • Templates 模板,可替换模板文件中的变量并实现一些简单逻辑的文件
  • Handlers 和 notify 结合使用,由特定条件触发的操作,满足条件方才执行,否则不执行
  • tags 标签 指定某条任务执行,用于选择运行playbook中的部分代码。ansible具有幂等性,因此会自动跳过没有变化的部分,即便如此,有些代码为测试其确实没有发生变化的时间依然会非常地长。此时,如果确信其没有变化,就可以通过tags跳过此些代码片断

hosts 组件

Hosts:playbook中的每一个play的目的都是为了让特定主机以某个指定的用户身份执行任务。hosts用于指定要执行指定任务的主机,须事先定义在主机清单中

one.example.com
one.example.com:two.example.com
192.168.1.50
192.168.1.*
Websrvs:dbsrvs      #或者,两个组的并集
Websrvs:&dbsrvs     #与,两个组的交集
webservers:!phoenix  #在websrvs组,但不在dbsrvs组

案例:

- hosts: websrvs:appsrvs

remote_user 组件

remote_user: 可用于Host和task中。也可以通过指定其通过sudo的方式在远程主机上执行任务,其可用于play全局或某任务;此外,甚至可以在sudo时使用sudo_user指定sudo时切换的用户

- hosts: websrvs
  remote_user: root

  tasks:
    - name: test connection
      ping:
      remote_user: magedu
      sudo: yes                 #默认sudo为root
      sudo_user:wang        #sudo为wang

task列表和action组件

play的主体部分是task list,task list中有一个或多个task,各个task 按次序逐个在hosts中指定的所有主机上执行,即在所有主机上完成第一个task后,再开始第二个task
task的目的是使用指定的参数执行模块,而在模块参数中可以使用变量。模块执行是幂等的,这意味着多次执行是安全的,因为其结果均一致
每个task都应该有其name,用于playbook的执行结果输出,建议其内容能清晰地描述任务执行步骤。如果未提供name,则action的结果将用于输出

task两种格式:
(1) action: module arguments
(2) module: arguments 建议使用

注意:shell和command模块后面跟命令,而非key=value

范例:

---
- hosts: websrvs
  remote_user: root
  tasks:
    - name: install httpd
      yum: name=httpd 
    - name: start httpd
      service: name=httpd state=started enabled=yes

其它组件

某任务的状态在运行后为changed时,可通过“notify”通知给相应的handlers
任务可以通过"tags“打标签,可在ansible-playbook命令上使用-t指定进行调用

ShellScripts VS Playbook 案例

#SHELL脚本实现
#!/bin/bash
# 安装Apache
yum install --quiet -y httpd 
# 复制配置文件
cp /tmp/httpd.conf /etc/httpd/conf/httpd.conf
cp/tmp/vhosts.conf /etc/httpd/conf.d/
# 启动Apache,并设置开机启动
systemctl enable --now httpd 

#Playbook实现
---
- hosts: websrvs
  remote_user: root
  tasks:
    - name: "安装Apache"
      yum: name=httpd
    - name: "复制配置文件"
      copy: src=/tmp/httpd.conf dest=/etc/httpd/conf/
    - name: "复制配置文件"
      copy: src=/tmp/vhosts.conf dest=/etc/httpd/conf.d/
    - name: "启动Apache,并设置开机启动"
      service: name=httpd state=started enabled=yes

ansible企业案例

playbook 命令

格式

ansible-playbook <filename.yml> ... [options]

常见选项


-C --check          #只检测可能会发生的改变,但不真正执行操作 --list-hosts        #列出运行任务的主机 --list-tags         #列出tag --list-tasks        #列出task --limit 主机列表      #只针对主机列表中的主机执行 -v -vv  -vvv        #显示过程


范例

ansible-playbook  file.yml  --check #只检测
ansible-playbook  file.yml  
ansible-playbook  file.yml  --limit websrvs

Playbook 初步

利用 playbook 创建 mysql 用户

范例:mysql_user.yml

---
- hosts: dbsrvs
  remote_user: root

  tasks:
    - {name: create group, group: name=mysql system=yes gid=306}
    - name: create user
      user: name=mysql shell=/sbin/nologin system=yes group=mysql uid=306 home=/data/mysql create_home=no

 

利用 playbook 安装 nginx

范例:install_nginx.yml

---
# install nginx 
- hosts: websrvs
  remote_user: root  
  tasks:
    - name: add group nginx
      user: name=nginx state=present
    - name: add user nginx
      user: name=nginx state=present group=nginx
    - name: Install Nginx
      yum: name=nginx state=present
    - name: web page
      copy: src=files/index.html dest=/usr/share/nginx/html/index.html
    - name: Start Nginx
      service: name=nginx state=started enabled=yes

利用 playbook 安装和卸载 httpd

范例:install_httpd.yml

---
#install httpd 
- hosts: websrvs
  remote_user: root
  gather_facts: no

  tasks:
    - name: Install httpd
      yum: name=httpd state=present
    - name: Install configure file
      copy: src=files/httpd.conf dest=/etc/httpd/conf/
    - name: web html
      copy: src=files/index.html  dest=/var/www/html/
    - name: start service
      service: name=httpd state=started enabled=yes

ansible-playbook   install_httpd.yml --limit 10.0.0.8

范例:remove_httpd.yml

#remove_httpd.yml
---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: remove httpd package
      yum: name=httpd state=absent
    - name: remove apache user 
      user: name=apache state=absent
    - name: remove config file
      file: name=/etc/httpd  state=absent
    - name: remove web html
      file: name=/var/www/html/index.html state=absent

利用 playbook 安装mysql

范例:安装mysql-5.6.46-linux-glibc2.12

[root@ansible ~]#ls -l /data/ansible/files/mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz 
-rw-r--r-- 1 root root 403177622 Dec  4 13:05 /data/ansible/files/mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz

[root@ansible ~]#cat /data/ansible/files/my.cnf 
[mysqld]
socket=/tmp/mysql.sock
user=mysql
symbolic-links=0
datadir=/data/mysql
innodb_file_per_table=1
log-bin
pid-file=/data/mysql/mysqld.pid

[client]
port=3306
socket=/tmp/mysql.sock

[mysqld_safe]
log-error=/var/log/mysqld.log

[root@ansible ~]#cat /data/ansible/files/secure_mysql.sh 
#!/bin/bash
/usr/local/mysql/bin/mysql_secure_installation <<EOF

y
magedu
magedu
y
y
y
y
EOF

[root@ansible ~]#tree /data/ansible/files/
/data/ansible/files/
├── my.cnf
├── mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz
└── secure_mysql.sh

0 directories, 3 files

[root@ansible ~]#cat /data/ansible/install_mysql.yml
---
# install mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz
- hosts: dbsrvs
  remote_user: root
  gather_facts: no

  tasks:
    - name: install packages
      yum: name=libaio,perl-Data-Dumper,perl-Getopt-Long
    - name: create mysql group
      group: name=mysql gid=306 
    - name: create mysql user
      user: name=mysql uid=306 group=mysql shell=/sbin/nologin system=yes create_home=no home=/data/mysql
    - name: copy tar to remote host and file mode 
      unarchive: src=/data/ansible/files/mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz dest=/usr/local/ owner=root group=root 
    - name: create linkfile  /usr/local/mysql 
      file: src=/usr/local/mysql-5.6.46-linux-glibc2.12-x86_64 dest=/usr/local/mysql state=link
    - name: data dir
      shell: chdir=/usr/local/mysql/  ./scripts/mysql_install_db --datadir=/data/mysql --user=mysql
      tags: data
    - name: config my.cnf
      copy: src=/data/ansible/files/my.cnf  dest=/etc/my.cnf 
    - name: service script
      shell: /bin/cp /usr/local/mysql/support-files/mysql.server /etc/init.d/mysqld
    - name: enable service
      shell: /etc/init.d/mysqld start;chkconfig --add mysqld;chkconfig mysqld on  
      tags: service
    - name: PATH variable
      copy: content='PATH=/usr/local/mysql/bin:$PATH' dest=/etc/profile.d/mysql.sh
    - name: secure script
      script: /data/ansible/files/secure_mysql.sh
      tags: script

范例:install_mariadb.yml

---
#Installing MariaDB Binary Tarballs
- hosts: dbsrvs
  remote_user: root
  gather_facts: no

  tasks:
    - name: create group
      group: name=mysql gid=27 system=yes
    - name: create user
      user: name=mysql uid=27 system=yes group=mysql shell=/sbin/nologin home=/data/mysql create_home=no
    - name: mkdir datadir
      file: path=/data/mysql owner=mysql group=mysql state=directory
    - name: unarchive package
      unarchive: src=/data/ansible/files/mariadb-10.2.27-linux-x86_64.tar.gz dest=/usr/local/ owner=root group=root
    - name: link
      file: src=/usr/local/mariadb-10.2.27-linux-x86_64 path=/usr/local/mysql state=link 
    - name: install database
      shell: chdir=/usr/local/mysql   ./scripts/mysql_install_db --datadir=/data/mysql --user=mysql
    - name: config file
      copy: src=/data/ansible/files/my.cnf  dest=/etc/ backup=yes
    - name: service script
      shell: /bin/cp  /usr/local/mysql/support-files/mysql.server  /etc/init.d/mysqld
    - name: start service
      service: name=mysqld state=started enabled=yes
    - name: PATH variable
      copy: content='PATH=/usr/local/mysql/bin:$PATH' dest=/etc/profile.d/mysql.sh

Playbook中使用变量

量名:仅能由字母、数字和下划线组成,且只能以字母开头

变量定义:

variable=value

范例:

http_port=80

变量调用方式:

通过{{ variable_name }} 调用变量,且变量名前后建议加空格,有时用“{{ variable_name }}”才生效

变量来源:

1.ansible 的 setup facts 远程主机的所有变量都可直接调用

2.通过命令行指定变量,优先级最高

ansible-playbook -e varname=value

3.在playbook文件中定义

vars:
     - var1: value1
     - var2: value2

4.在独立的变量YAML文件中定义

- hosts: all
     vars_files:
       - vars.yml

5.在 /etc/ansible/hosts 中定义

主机(普通)变量:主机组中主机单独定义,优先级高于公共变量
组(公共)变量:针对主机组中所有主机定义统一变量

6.在role中定义

使用 setup 模块中变量

本模块自动在playbook调用,不要用ansible命令调用

案例:使用setup变量

---
#var.yml
- hosts: all
  remote_user: root
  gather_facts: yes

  tasks:
    - name: create log file
      file: name=/data/{{ ansible_nodename }}.log state=touch owner=wang mode=600

ansible-playbook  var.yml

在playbook 命令行中定义变量

范例:

vim var2.yml
---
- hosts: websrvs
  remote_user: root
  tasks:
    - name: install package
      yum: name={{ pkname }} state=present

ansible-playbook  –e pkname=httpd  var2.yml

在playbook文件中定义变量

范例:

vim var3.yml
---
- hosts: websrvs
  remote_user: root
  vars:
    - username: user1
    - groupname: group1

  tasks:
    - name: create group
      group: name={{ groupname }} state=present
    - name: create user
      user: name={{ username }} group={{ groupname }} state=present

ansible-playbook -e "username=user2 groupname=group2”  var3.yml

使用变量文件

可以在一个独立的playbook文件中定义变量,在另一个playbook文件中引用变量文件中的变量,比playbook中定义的变量优化级高

vim vars.yml
---
# variables file
package_name: mariadb-server
service_name: mariadb

vim  var4.yml
---
#install package and start service
- hosts: dbsrvs
  remote_user: root
  vars_files:
    - /root/vars.yml

  tasks:
    - name: install package
      yum: name={{ package_name }}
      tags: install
    - name: start service
      service: name={{ service_name }} state=started enabled=yes

范例:

cat  vars2.yml
---
var1: httpd
var2: nginx

cat  var5.yml
---         
- hosts: web
  remote_user: root
  vars_files:
    - vars2.yml

   tasks:
     - name: create httpd log
       file: name=/app/{{ var1 }}.log state=touch
     - name: create nginx log
       file: name=/app/{{ var2 }}.log state=touch

主机清单文件中定义变量

主机变量

在inventory 主机清单文件中为指定的主机定义变量以便于在playbook中使用

范例:

[websrvs]
www1.magedu.com http_port=80 maxRequestsPerChild=808
www2.magedu.com http_port=8080 maxRequestsPerChild=909

组(公共)变量

在inventory 主机清单文件中赋予给指定组内所有主机上的在playbook中可用的变量,如果和主机变是同名,优先级低于主机变量

范例:

[websrvs]
www1.magedu.com
www2.magedu.com

[websrvs:vars]
ntp_server=ntp.magedu.com
nfs_server=nfs.magedu.com

范例:

vim /etc/ansible/hosts

[websrvs]
192.168.0.101 hname=www1 domain=magedu.io
192.168.0.102 hname=www2 

[websvrs:vars]
mark=“-”
domain=magedu.org

ansible  websvrs  –m hostname –a ‘name={{ hname }}{{ mark }}{{ domain }}’
bash
#命令行指定变量: 
ansible  websvrs  –e domain=magedu.cn –m hostname –a    ‘name={{ hname }}{{ mark }}{{ domain }}’

 

template 模板

模板是一个文本文件,可以做为生成文件的模版,并且模板文件中还可嵌套jinja语法

jinja2语言

网站:https://jinja.palletsprojects.com/en/2.11.x/

jinja2 语言使用字面量,有下面形式:
字符串:使用单引号或双引号

数字:整数,浮点数
 列表:[item1, item2, …]
 元组:(item1, item2, …)
 字典:{key1:value1, key2:value2, …}
 布尔型:true/false
 算术运算:+, -, *, /, //, %, **
 比较操作:==, !=, >, >=, <, <=
 逻辑运算:and,or,not
 流表达式:For,If,When

字面量:

表达式最简单的形式就是字面量。字面量表示诸如字符串和数值的 Python 对象。如“Hello World”
双引号或单引号中间的一切都是字符串。无论何时你需要在模板中使用一个字符串(比如函数调用、过滤器或只是包含或继承一个模板的参数),如42,42.23
数值可以为整数和浮点数。如果有小数点,则为浮点数,否则为整数。在 Python 里, 42 和 42.0 是不一样的

算术运算:

Jinja 允许用计算值。支持下面的运算符

+:把两个对象加到一起。通常对象是素质,但是如果两者是字符串或列表,你可以用这 种方式来衔接它们。无论如何这不是首选的连接字符串的方式!连接字符串见 ~ 运算符。 {{ 1 + 1 }} 等于 2
 -:用第一个数减去第二个数。 {{ 3 – 2 }} 等于 1
 /:对两个数做除法。返回值会是一个浮点数。 {{ 1 / 2 }} 等于 {{ 0.5 }}
 //:对两个数做除法,返回整数商。 {{ 20 // 7 }} 等于 2
 %:计算整数除法的余数。 {{ 11 % 7 }} 等于 4
:用右边的数乘左边的操作数。 {{ 2 2 }} 会返回 4 。也可以用于重 复一个字符串多次。 {{ ‘=’ 80 }} 会打印 80 个等号的横条\
 *:取左操作数的右操作数次幂。 {{ 2**3 }} 会返回 8

比较操作符
== 比较两个对象是否相等
!= 比较两个对象是否不等

如果左边大于右边,返回 true
= 如果左边大于等于右边,返回 true
< 如果左边小于右边,返回 true
<= 如果左边小于等于右边,返回 true

逻辑运算符
对于 if 语句,在 for 过滤或 if 表达式中,它可以用于联合多个表达式
and 如果左操作数和右操作数同为真,返回 true
or 如果左操作数和右操作数有一个为真,返回 true
not 对一个表达式取反
(expr)表达式组
true / false true 永远是 true ,而 false 始终是 false

template

template功能:可以根据和参考模块文件,动态生成相类似的配置文件
template文件必须存放于templates目录下,且命名为 .j2 结尾
yaml/yml 文件需和templates目录平级,目录结构如下示例:
./
├── temnginx.yml
└── templates
└── nginx.conf.j2

范例:利用template 同步nginx配置文件

#准备templates/nginx.conf.j2文件
vim temnginx.yml
---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: template config to remote hosts
      template: src=nginx.conf.j2 dest=/etc/nginx/nginx.conf

 ansible-playbook temnginx.yml

template变更替换

范例:

#修改文件nginx.conf.j2 
mkdir templates
vim templates/nginx.conf.j2
worker_processes {{ ansible_processor_vcpus }};

vim temnginx2.yml
---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: install nginx
      yum: name=nginx
    - name: template config to remote hosts
      template: src=nginx.conf.j2 dest=/etc/nginx/nginx.conf 
    - name: start service
      service: name=nginx state=started enable=yes

ansible-playbook temnginx2.yml

template算术运算

范例:

vim nginx.conf.j2 
worker_processes {{ ansible_processor_vcpus**2 }};    
worker_processes {{ ansible_processor_vcpus+2 }};

范例:

[root@ansible ansible]#vim templates/nginx.conf.j2
worker_processes {{ ansible_processor_vcpus**3 }};

[root@ansible ansible]#cat templnginx.yml
---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: install nginx
      yum: name=nginx
    - name: template config to remote hosts
      template: src=nginx.conf.j2 dest=/etc/nginx/nginx.conf
      notify: restart nginx
    - name: start service
      service: name=nginx state=started enabled=yes

  handlers:
    - name: restart nginx
      service: name=nginx state=restarted

ansible-playbook  templnginx.yml --limit 10.0.0.8

template中使用流程控制 for 和 if

template中也可以使用流程控制 for 循环和 if 条件判断,实现动态生成文件功能

范例

#temlnginx2.yml
---
- hosts: websrvs
  remote_user: root
  vars:
    nginx_vhosts:
      - 81
      - 82
      - 83
  tasks:
    - name: template config
      template: src=nginx.conf.j2 dest=/data/nginx.conf

#templates/nginx.conf2.j2
{% for vhost in  nginx_vhosts %}
server {
   listen {{ vhost }}
}
{% endfor %}

ansible-playbook -C  templnginx2.yml  --limit 10.0.0.8

#生成的结果:
server {
   listen 81   
}
server {
   listen 82   
}
server {
   listen 83   
}

范例:

#temlnginx3.yml
---
- hosts: websrvs
  remote_user: root
  vars:
    nginx_vhosts:
      - listen: 8080
  tasks:
    - name: config file
      template: src=nginx.conf3.j2 dest=/data/nginx3.conf

#templates/nginx.conf3.j2
{% for vhost in nginx_vhosts %}   
server {
  listen {{ vhost.listen }}
}
{% endfor %}

ansible-playbook   templnginx3.yml  --limit 10.0.0.8

#生成的结果
server {
  listen 8080  
}

范例:

#templnginx4.yml
- hosts: websrvs
  remote_user: root
  vars:
    nginx_vhosts:
      - listen: 8080
        server_name: "web1.magedu.com"
        root: "/var/www/nginx/web1/"
      - listen: 8081
        server_name: "web2.magedu.com"
        root: "/var/www/nginx/web2/"
      - {listen: 8082, server_name: "web3.magedu.com", root: "/var/www/nginx/web3/"}
  tasks:
    - name: template config 
      template: src=nginx.conf4.j2 dest=/data/nginx4.conf

# templates/nginx.conf4.j2
{% for vhost in nginx_vhosts %}
server {
   listen {{ vhost.listen }}
   server_name {{ vhost.server_name }}
   root {{ vhost.root }}  
}
{% endfor %}

ansible-playbook  templnginx4.yml --limit 10.0.0.8

#生成结果:
server {
    listen 8080
    server_name web1.magedu.com
    root /var/www/nginx/web1/  
}
server {
    listen 8081
    server_name web2.magedu.com
    root /var/www/nginx/web2/  
}
server {
    listen 8082
    server_name web3.magedu.com
    root /var/www/nginx/web3/  
}

在模版文件中还可以使用 if条件判断,决定是否生成相关的配置信息

范例:

#templnginx5.yml
- hosts: websrvs
  remote_user: root
  vars:
    nginx_vhosts:
      - web1:
        listen: 8080
        root: "/var/www/nginx/web1/"
      - web2:
        listen: 8080
        server_name: "web2.magedu.com"
        root: "/var/www/nginx/web2/"
      - web3:
        listen: 8080
        server_name: "web3.magedu.com"
        root: "/var/www/nginx/web3/"
  tasks:
    - name: template config to 
      template: src=nginx.conf5.j2 dest=/data/nginx5.conf

#templates/nginx.conf5.j2
{% for vhost in  nginx_vhosts %}
server {
   listen {{ vhost.listen }}
   {% if vhost.server_name is defined %}
server_name {{ vhost.server_name }}
   {% endif %}
root  {{ vhost.root }}
}
{% endfor %}

#生成的结果
server {
   listen 8080
   root  /var/www/nginx/web1/
}
server {
   listen 8080
   server_name web2.magedu.com
   root  /var/www/nginx/web2/
}
server {
   listen 8080
   server_name web3.magedu.com
   root  /var/www/nginx/web3/
}

playbook使用 when

when语句,可以实现条件测试。如果需要根据变量、facts或此前任务的执行结果来做为某task执行与否的前提时要用到条件测试,通过在task后添加when子句即可使用条件测试,jinja2的语法格式

范例:

---
- hosts: websrvs
  remote_user: root
  tasks:
    - name: "shutdown RedHat flavored systems"
      command: /sbin/shutdown -h now
      when: ansible_os_family == "RedHat"

范例:

---
- hosts: websrvs
  remote_user: root
  tasks:
    - name: add group nginx
      tags: user
      user: name=nginx state=present
    - name: add user nginx
      user: name=nginx state=present group=nginx
    - name: Install Nginx
      yum: name=nginx state=present
    - name: restart Nginx
      service: name=nginx state=restarted
      when: ansible_distribution_major_version == “6”

范例:

---
- hosts: websrvs
  remote_user: root
  tasks: 
    - name: install conf file to centos7
      template: src=nginx.conf.c7.j2 dest=/etc/nginx/nginx.conf
      when: ansible_distribution_major_version == "7"
    - name: install conf file to centos6
      template: src=nginx.conf.c6.j2 dest=/etc/nginx/nginx.conf
      when: ansible_distribution_major_version == "6"

playbook 使用迭代 with_items

迭代:当有需要重复性执行的任务时,可以使用迭代机制
对迭代项的引用,固定变量名为”item“
要在task中使用with_items给定要迭代的元素列表

列表元素格式:

  • 字符串
  • 字典

范例:

---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: add several users
      user: name={{ item }} state=present groups=wheel
      with_items:
        - testuser1
        - testuser2
#上面语句的功能等同于下面的语句
    - name: add user testuser1
      user: name=testuser1 state=present groups=wheel
    - name: add user testuser2
      user: name=testuser2 state=present groups=wheel

范例:

---
#remove mariadb server
- hosts: appsrvs:!192.168.38.8
  remote_user: root

  tasks:
    - name: stop service
      shell: /etc/init.d/mysqld stop
    - name:  delete files and dir
      file: path={{item}} state=absent
      with_items:
        - /usr/local/mysql
        - /usr/local/mariadb-10.2.27-linux-x86_64
        - /etc/init.d/mysqld
        - /etc/profile.d/mysql.sh
        - /etc/my.cnf
        - /data/mysql
    - name: delete user
      user: name=mysql state=absent remove=yes

范例:

---
- hosts:websrvs
  remote_user: root

  tasks
    - name: install some packages
      yum: name={{ item }} state=present
      with_items:
        - nginx
        - memcached
        - php-fpm

范例:

---
- hosts: websrvs
  remote_user: root
  tasks:
    - name: copy file
      copy: src={{ item }} dest=/tmp/{{ item }}
      with_items:
        - file1
        - file2
        - file3
    - name: yum install httpd
      yum: name={{ item }}  state=present 
      with_items:
        - apr
        - apr-util
        - httpd

迭代嵌套子变量:在迭代中,还可以嵌套子变量,关联多个变量在一起使用

示例:

---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: add some groups
      group: name={{ item }} state=present
      with_items:
        - nginx
        - mysql
        - apache
    - name: add some users
      user: name={{ item.name }} group={{ item.group }} state=present
      with_items:
        - { name: 'nginx', group: 'nginx' }
        - { name: 'mysql', group: 'mysql' }
        - { name: 'apache', group: 'apache' }

范例:

cat with_item2.yml
---
- hosts: websrvs
  remote_user: root

  tasks:
    - name: add some groups
      group: name={{ item }} state=present
      with_items:
        - g1
        - g2
        - g3
    - name: add some users
      user: name={{ item.name }} group={{ item.group }} home={{ item.home }} create_home=yes state=present
      with_items:
        - { name: 'user1', group: 'g1', home: '/data/user1' }
        - { name: 'user2', group: 'g2', home: '/data/user2' }
        - { name: 'user3', group: 'g3', home: '/data/user3' }

 

管理节点过多导致的超时问题解决方法

默认情况下,Ansible将尝试并行管理playbook中所有的机器。对于滚动更新用例,可以使用serial关键字定义Ansible一次应管理多少主机,还可以将serial关键字指定为百分比,表示每次并行执行的主机数占总数的比例

范例:

#vim test_serial.yml
---
- hosts: all
  serial: 2  #每次只同时处理2个主机
  gather_facts: False

  tasks:
    - name: task one
      comand: hostname
    - name: task two
      command: hostname

范例:

- name: test serail
  hosts: all
  serial: "20%"   #每次只同时处理20%的主机

 

roles角色

角色是ansible自1.2版本引入的新特性,用于层次性、结构化地组织playbook。roles能够根据层次型结构自动装载变量文件、tasks以及handlers等。要使用roles只需要在playbook中使用include指令即可。简单来讲,roles就是通过分别将变量、文件、任务、模板及处理器放置于单独的目录中,并可以便捷地include它们的一种机制。角色一般用于基于主机构建服务的场景中,但也可以是用于构建守护进程等场景中

运维复杂的场景:建议使用roles,代码复用度高

roles:多个角色的集合, 可以将多个的role,分别放至roles目录下的独立子目录中
roles/
mysql/
httpd/
nginx/
redis/

Ansible Roles目录编排

roles目录结构如下所示

ansible关闭firewalld ansible playbook 跳过_nginx

每个角色,以特定的层级目录结构进行组织

roles目录结构:
playbook.yml
roles/
project/
tasks/
files/
vars/
templates/
handlers/
default/
meta/

Roles各目录作用
roles/project/ :项目名称,有以下子目录

  • files/ :存放由copy或script模块等调用的文件
  • templates/:template模块查找所需要模板文件的目录
  • tasks/:定义task,role的基本元素,至少应该包含一个名为main.yml的文件;其它的文件需要在此文件中通过include进行包含
  • handlers/:至少应该包含一个名为main.yml的文件;其它的文件需要在此文件中通过include进行包含
  • vars/:定义变量,至少应该包含一个名为main.yml的文件;其它的文件需要在此文件中通过include进行包含
  • meta/:定义当前角色的特殊设定及其依赖关系,至少应该包含一个名为main.yml的文件,其它文件需在此文件中通过include进行包含
  • default/:设定默认变量时使用此目录中的main.yml文件,比vars的优先级低

创建 role

创建role的步骤
(1) 创建以roles命名的目录
(2) 在roles目录中分别创建以各角色名称命名的目录,如webservers等
(3) 在每个角色命名的目录中分别创建files、handlers、meta、tasks、templates和vars目录;用不到的目录可以创建为空目录,也可以不创建
(4) 在playbook文件中,调用各角色

针对大型项目使用Roles进行编排
范例:roles的目录结构

nginx-role.yml 
roles/
└── nginx 
     ├── files
     │    └── main.yml 
     ├── tasks
     │    ├── groupadd.yml 
     │    ├── install.yml 
     │    ├── main.yml 
     │    ├── restart.yml 
     │    └── useradd.yml 
     └── vars 
          └── main.yml

playbook调用角色

调用角色方法1:

---
- hosts: websrvs
  remote_user: root
  roles:
    - mysql
    - memcached
    - nginx


调用角色方法2:

键role用于指定角色名称,后续的k/v用于传递变量给角色

---
- hosts: all
  remote_user: root
  roles:
    - mysql
    - { role: nginx, username: nginx }

调用角色方法3:

还可基于条件测试实现角色调用

---
- hosts: all
  remote_user: root
  roles:
    - { role: nginx, username: nginx, when: ansible_distribution_major_version == ‘7’  }

roles 中 tags 使用

#nginx-role.yml
---
- hosts: websrvs
  remote_user: root
  roles:
    - { role: nginx ,tags: [ 'nginx', 'web' ] ,when: ansible_distribution_major_version == "6“ }
    - { role: httpd ,tags: [ 'httpd', 'web' ]  }
    - { role: mysql ,tags: [ 'mysql', 'db' ] }
    - { role: mariadb ,tags: [ 'mariadb', 'db' ] }

ansible-playbook --tags="nginx,httpd,mysql" nginx-role.yml

 

实战案例

 

案例1:实现 httpd 角色

#创建角色相关的目录
mkdir -pv /data/ansible/roles/httpd/{tasks,handlers,files}

#创建角色相关的文件
cd /data/ansible/roles/httpd/

vim tasks/main.yml
- include: group.yml
- include: user.yml
- include: install.yml
- include: config.yml
- include: index.yml
- include: service.yml

vim  tasks/user.yml
- name: create apache user
  user: name=apache system=yes shell=/sbin/nologin home=/var/www/ uid=80 group=apache

vim  tasks/group.yml
- name: create apache group
  group: name=apache system=yes gid=80

vim tasks/install.yml
- name: install httpd package
  yum: name=httpd

vim tasks/config.yml
- name: config file
  copy: src=httpd.conf dest=/etc/httpd/conf/ backup=yes
  notify: restart

vim tasks/index.yml
- name: index.html
  copy: src=index.html dest=/var/www/html/

vim tasks/service.yml
- name: start service
  service: name=httpd state=started enabled=yes

vim handlers/main.yml
- name: restart
  service: name=httpd state=restarted

#在files目录下准备两个文件
ls files/
httpd.conf index.html

tree /data/ansible/roles/httpd/
/data/ansible/roles/httpd/
├── files
│   ├── httpd.conf
│   └── index.html
├── handlers
│   └── main.yml
└── tasks
    ├── config.yml
    ├── group.yml
    ├── index.yml
    ├── install.yml
    ├── main.yml
    ├── service.yml
    └── user.yml

3 directories, 10 files

#在playbook中调用角色
vim  /data/ansible/role_httpd.yml
---
# httpd role
- hosts: websrvs
  remote_user: root

  roles:
    - httpd

#运行playbook
ansible-playbook  /data/ansible/role_httpd.yml

案例2:实现 nginx 角色

mkdir -pv  /data/ansible/roles/nginx/{tasks,handlers,templates,vars}

#创建task文件
cd /data/ansible/roles/nginx/

vim tasks/main.yml 
- include: install.yml
- include: config.yml
- include: index.yml
- include: service.yml

vim  tasks/install.yml 
- name: install
  yum: name=nginx 

vim tasks/config.yml 
- name: config file for centos7
  template: src=nginx7.conf.j2 dest=/etc/nginx/nginx.conf
  when: ansible_distribution_major_version=="7"
  notify: restart
- name: config file for centos8
  template: src=nginx8.conf.j2 dest=/etc/nginx/nginx.conf
  when: ansible_distribution_major_version=="8"
  notify: restart

vim  tasks/index.yml 
- name: index.html
  copy: src=roles/httpd/files/index.html dest=/usr/share/nginx/html/

vim tasks/service.yml 
- name: start service
  service: name=nginx state=started enabled=yes

#创建handler文件
cat handlers/main.yml 
- name: restart
  service: name=nginx state=restarted

#创建两个template文件
cat templates/nginx7.conf.j2
...省略...
user {{user}};
worker_processes {{ansible_processor_vcpus+3}};   #修改此行
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
...省略...

cat templates/nginx8.conf.j2
...省略...
user nginx;
worker_processes {{ansible_processor_vcpus**3}};  #修改此行
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
...省略...

#创建变量文件
vim vars/main.yml 
user: daemon

#目录结构如下

tree /data/ansible/roles/nginx/
/data/ansible/roles/nginx/
├── handlers
│   └── main.yml
├── tasks
│   ├── config.yml
│   ├── file.yml
│   ├── install.yml
│   ├── main.yml
│   └── service.yml
├── templates
│   ├── nginx7.conf.j2
│   └── nginx8.conf.j2
└── vars
    └── main.yml

4 directories, 9 files

#在playbook中调用角色
vim /data/ansible/role_nginx.yml 
---
#nginx role 
- hosts: websrvs

  roles:
    - role: nginx

#运行playbook
ansible-playbook  /data/ansible/role_nginx.yml

案例3:实现 memcached 角色

mkdir -pv  /data/ansible/roles/memcached/{tasks,templates}

cd /data/ansible/roles/memcached
vim tasks/main.yml 
- include: install.yml
- include: config.yml
- include: service.yml

vim tasks/install.yml 
- name: install
  yum: name=memcached

vim tasks/config.yml 
- name: config file
  template: src=memcached.j2  dest=/etc/sysconfig/memcached

vim tasks/service.yml 
- name: service
  service: name=memcached state=started enabled=yes

vim templates/memcached.j2 
PORT="11211"
USER="memcached"
MAXCONN="1024"
CACHESIZE="{{ansible_memtotal_mb//4}}"
OPTIONS=""

tree /data/ansible/roles/memcached/
/data/ansible/roles/memcached/
├── tasks
│   ├── config.yml
│   ├── install.yml
│   ├── main.yml
│   └── service.yml
└── templates
    └── memcached.j2

2 directories, 5 files

vim /data/ansible/role_memcached.yml 
---
- hosts: appsrvs

  roles:
    - role: memcached

ansible-play /data/ansible/role_memcached.yml

案例4:实现 mysql 5.6 的角色

[root@ansible ~]#cat /data/ansible/roles/mysql/files/my.cnf 
[mysqld]
socket=/tmp/mysql.sock
user=mysql
symbolic-links=0
datadir=/data/mysql
innodb_file_per_table=1
log-bin
pid-file=/data/mysql/mysqld.pid

[client]
port=3306
socket=/tmp/mysql.sock

[mysqld_safe]
log-error=/var/log/mysqld.log

[root@ansible ~]#cat /data/ansible/roles/mysql/files/secure_mysql.sh 
#!/bin/bash
/usr/local/mysql/bin/mysql_secure_installation <<EOF

y
magedu
magedu
y
y
y
y
EOF

[root@ansible ~]#chmod +x  /data/ansible/roles/mysql/files/secure_mysql.sh

[root@ansible ~]#ls /data/ansible/roles/mysql/files/
my.cnf  mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz  secure_mysql.sh

[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/main.yml
- include: install.yml
- include: group.yml
- include: user.yml
- include: unarchive.yml
- include: link.yml
- include: data.yml
- include: config.yml
- include: service.yml
- include: path.yml
- include: secure.yml

[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/install.yml 
- name: install packages                                            
  yum: name=libaio,perl-Data-Dumper,perl-Getopt-Long
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/group.yml 
- name: create mysql group
  group: name=mysql gid=306
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/user.yml 
- name: create mysql user
  user: name=mysql uid=306 group=mysql shell=/sbin/nologin system=yes create_home=no home=/data/mysql
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/unarchive.yml 
- name: copy tar to remote host and file mode 
  unarchive: src=mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz dest=/usr/local/ owner=root group=root
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/link.yml 
- name: mkdir /usr/local/mysql 
  file: src=/usr/local/mysql-5.6.46-linux-glibc2.12-x86_64 dest=/usr/local/mysql state=link
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/data.yml 
- name: data dir
  shell: chdir=/usr/local/mysql/  ./scripts/mysql_install_db --datadir=/data/mysql --user=mysql
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/config.yml 
- name: config my.cnf
  copy: src=my.cnf  dest=/etc/my.cnf 
[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/service.yml 
- name: service script
  shell: /bin/cp /usr/local/mysql/support-files/mysql.server /etc/init.d/mysqld;chkconfig --add mysqld;chkconfig mysqld on;/etc/init.d/mysqld start

[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/path.yml 
- name: PATH variable
  copy: content='PATH=/usr/local/mysql/bin:$PATH' dest=/etc/profile.d/mysql.sh  

[root@ansible ~]#cat /data/ansible/roles/mysql/tasks/secure.yml 
- name: secure script
  script: secure_mysql.sh

[root@ansible ~]#tree /data/ansible/roles/mysql/
/data/ansible/roles/mysql/
├── files
│   ├── my.cnf
│   ├── mysql-5.6.46-linux-glibc2.12-x86_64.tar.gz
│   └── secure_mysql.sh
└── tasks
    ├── config.yml
    ├── data.yml
    ├── group.yml
    ├── install.yml
    ├── link.yml
    ├── main.yml
    ├── path.yml
    ├── secure.yml
    ├── service.yml
    ├── unarchive.yml
    └── user.yml

2 directories, 14 files

[root@ansible ~]#cat /data/ansible/mysql_roles.yml
- hosts: dbsrvs
  remote_user: root

  roles:
    - {role: mysql,tags: ["mysql","db"]}
    - {role: nginx,tage: ["nginx","web"]}

[root@ansible ~]#ansible-playbook -t mysql /data/ansible/mysql_roles.yml

案例5 :实现多角色的选择

vim /data/ansible/role_httpd_nginx.yml 
---
- hosts: websrvs

  roles:
    - {role: httpd,tags: [httpd,web], when: ansible_distribution_major_version=="7" }
    - {role: nginx,tags: [nginx,web], when: ansible_distribution_major_version=="8" }

ansible-playbook -t nginx /data/ansible/role_httpd_nginx.yml