Table of contents
1. Ansible script playbook script
1.1 Composition of playbooks
(1) Tasks: Tasks, that is, calling ansible templates through tasks to organize multiple operations in a playbook
(2) Variables: variables
(3) Templates: templates
(4) Handlers: processors, when the changed state conditions are met , (notify) triggers the execution of the operation
(5) Roles: role
2. Script writing experiment
vim test1.yaml
--- #yaml文件以---开头，以表明这是一个yaml文件，可省略
- name: first play #定义一个play的名称，可省略
gather_facts: false #设置不进行facts信息收集，这可以加快执行速度，可省略
hosts: webservers #指定要执行任务的被管理主机组，如多个主机组用冒号分隔
remote_user: root #指定被管理主机上执行任务的用户
tasks: #定义任务列表，任务列表中的各任务按次序逐个在hosts中指定的主机上执行
- name: test connection #自定义任务名称
ping: #使用 module: [options] 格式来定义一个任务
- name: disable selinux
command: '/sbin/setenforce 0' #command模块和shell模块无需使用key=value格式
ignore_errors: True #如执行命令的返回值不为0，就会报错，tasks停止，可使用ignore_errors忽略失败的任务
- name: disable firewalld
service: name=firewalld state=stopped #使用 module: options 格式来定义任务，option使用key=value格式
- name: install httpd
yum: name=httpd state=latest
- name: install configuration file for httpd
copy: src=/opt/httpd.conf dest=/etc/httpd/conf/httpd.conf #这里需要一个事先准备好的/opt/httpd.conf文件
notify: "restart httpd" #如以上操作后为changed的状态时，会通过notify指定的名称触发对应名称的handlers操作
- name: start httpd service
service: enabled=true name=httpd state=started
handlers: #handlers中定义的就是任务，此处handlers中的任务使用的是service模块
- name: restart httpd #notify和handlers中任务的名称必须一致
service: name=httpd state=restarted
##Ansible在执行完某个任务之后并不会立即去执行对应的handler，而是在当前play中所有普通任务都执行完后再去执行handler，这样的好处是可以多次触发notify，但最后只执行一次对应的handler，从而避免多次重启。
run playbook
ansible-playbook test1.yaml
//补充参数：
-k（–ask-pass）：用来交互输入ssh密码
-K（-ask-become-pass）：用来交互输入sudo密码
-u：指定用户
ansible-playbook test1.yaml --syntax-check #检查yaml文件的语法是否正确
ansible-playbook test1.yaml --list-task #检查tasks任务
ansible-playbook test1.yaml --list-hosts #检查生效的主机
ansible-playbook test1.yaml --start-at-task='install httpd' #指定从某个task开始运行
2.1 Definition and reference variables
- name: second play
hosts: dbservers
remote_user: root
vars: #定义变量
- groupname: mysql #格式为 key: value
- username: nginx
tasks:
- name: create group
group: name={
{
groupname}} system=yes gid=306 #使用 {
{key}} 引用变量的值
- name: create user
user: name={
{
username}} uid=306 group={
{
groupname}}
- name: copy file
copy: content="{
{ansible_default_ipv4}}" dest=/opt/vars.txt #在setup模块中可以获取facts变量信息
ansible-playbook test1.yaml -e "username=nginx" #在命令行里定义变量
2.2 Use remote host sudo to switch users
- hosts: dbservers
remote_user: zhangsan
become: yes #2.6版本以后的参数，之前是sudo，意思为切换用户运行
become_user: root #指定sudo用户为root
执行playbook时：ansible-playbook test1.yml -k -K
2.3 whenn condition judgment
- name: three play
hosts: all
remote_user: root
tasks:
- name: create file
file: path=/opt/abc.txt state=touch
when: ansible_default_ipv4.address=="192.168.243.103" #通过facts收集的信息过滤出匹配的主机,when中的变量名字，不需要手动加{
{}}
或
when: inventory_hostname == "<主机名>"
ansible-playbook test2.yaml
2.4 Iteration
- Ansible provides a variety of loop structures, generally named with_items, which is equivalent to the loop loop.
- name: play1
hosts: dbservers
gather_facts: false
tasks:
- name: create file
file:
path: "{
{item}}"
state: touch
with_items: [ /opt/a, /opt/b, /opt/c, /opt/d ]
- name: play2
hosts: dbservers
gather_facts: false
vars:
test:
- /tmp/test1
- /tmp/test2
- /tmp/test3
- /tmp/test4
tasks:
- name: create directories
file:
path: "{
{item}}"
state: directory
with_items: "{
{test}}"
- name: play3
hosts: dbservers
gather_facts: false
tasks:
- name: add users
user: name={
{
item.name}} state=present groups={
{
item.groups}}
with_items:
- name: test1
groups: wheel
- name: test2
groups: root
或
with_items:
- {
name: 'test1', groups: 'wheel'}
- {
name: 'test2', groups: 'root'}
ansible-playbook test3.yaml
Three, Templates template
- Jinja is a Python-based templating engine. The Template class is an important component of Jinja, which can be regarded as a compiled template file, used to generate target text, and pass Python variables to the template to replace the tags in the template.
1. First prepare a template template file with the suffix .j2, and set the referenced variables
cp /etc/httpd/conf/httpd.conf /opt/httpd.conf.j2
vim /opt/httpd.conf.j2
Listen {
{
http_port}} #42行，修改
ServerName {
{
server_name}} #95行，修改
DocumentRoot "{
{root_dir}}" #119行，修改
2. Modify the host list file, use the host variable to define a variable with the same variable name but different values
vim /etc/ansible/hosts
[webservers]
192.168.80.11 http_port=192.168.80.11:80 server_name=www.accp.com:80 root_dir=/etc/httpd/htdocs
[dbservers]
192.168.80.12 http_port=192.168.80.12:80 server_name=www.benet.com:80 root_dir=/etc/httpd/htdocs
3. Write playbook
vim apache.yaml
---
- hosts: all
remote_user: root
vars:
- package: httpd
- service: httpd
tasks:
- name: install httpd package
yum: name={
{
package}} state=latest
- name: install configure file
template: src=/opt/httpd.conf.j2 dest=/etc/httpd/conf/httpd.conf #使用template模板
notify:
- restart httpd
- name: create root dir
file: path=/etc/httpd/htdocs state=directory
- name: start httpd server
service: name={
{
service}} enabled=true state=started
handlers:
- name: restart httpd
service: name={
{
service}} state=restarted
ansible-playbook apache.yaml
4. Tags template
- You can define "tags" for one or some tasks in a playbook. When executing this playbook, use the –tags option through the ansible-playbook command to run only the specified tasks.
The playbook also provides a special tags for always. The effect is that when using always as the task of tags, no matter which tags are executed, the tags defined with always will be executed.
- name: serve play
remote_user: root
hosts: webservers
tasks:
- name: touch ddd,txt
file: path=/opt/ddd.txt state=touch
tags: #标签为ddd当命令tags标签为ddd，或者没有标签才执行
- ddd
- name: touch 123.txt
file: path=/opt/123.txt state=touch
tags:
- always #alwats表示都执行
- name: touch abc.txt
file: path=/opt/abc.txt state=touch
tags:
- aaa #同上
