一、循环
循环迭代任务
1.简单循环
loop: ##赋值列表
- value1
- value2
- ...
{{item}} ##迭代变量名称
#实例#
---
- name: create file
hosts: 172.25.0.254
tasks:
- name: file module
file:
name: /mnt/{{item}}
state: present
loop:
- westos_file1
- westos_file2
2.循环散列或字典列表
---
- name: create file
hosts: 172.25.0.254
tasks:
- name: file module
service:
name: "{{ item.name}}"
state: "{{ item.state }}"
loop:
- name: httpd
state: started
- name: vsftpd
state: stopped
二、条件
when:
- 条件1
- 条件2
#条件判断#
= value == "字符串",value == 数字
< value < 数字
> value > 数字
<= value <= 数字
>= value >= 数字
!= value != 数字
is defined value value is defined 变量存在
is not defined value is not defined 变量不存在
in value is in value 变量为
not in value is not in value 变量不为
bool变量 为true value value的值为true
bool变量 false not value value的值为false
value in value2 value的值在value2列表中
#多条条件组合#
when:
条件1 and 条件2
- 条件1
- 条件2
when:
条件1 or 条件2
when: >
条件1
or
条件2
true和false
三、触发器
notify: 触发器当遇到更改是触发handlers
handlers: 触发器触发后执行的动作
#实例#
---
- name: create virtualhost for web server
hosts: 172.25.0.254
vars_files:
./vhost_list.yml
tasks:
- name: create document
file:
path: "{{web2.document}}"
state: directory
- name: create vhost.conf
copy:
dest: /etc/httpd/conf.d/vhost.conf
content:
"<VirtualHost *:{{web1.port}}>\n\tServerName {{web1.name}}\n\tDocumentRoot
{{web1.document}}\n\tCustomLog logs/{{web1.name}}.log combined\n</VirtualHost>\n\n<VirtualHost *:
{{web2.port}}>\n\tServerName {{web2.name}}\n\tDocumentRoot {{web2.document}}\n\tCustomLog logs/
{{web2.name}}.log combined\n</VirtualHost>"
notify:
restart apache
handlers:
- name: restart apache
service:
name: httpd
state: restarted
四、处理失败任务
1.ignore_errors
#作用:
当play遇到任务失败时会终止
ignore_errors: yes 将会忽略任务失败使下面的任务继续运行
#实例#
- name: check file play
hosts: all
tasks:
- name: check file
shell:
test -e /mnt/file
ignore_errors: yes
register: check_state
- name: show message
debug:
msg: hello world
2.force_handlers
#作用:
#当任务失败后play被终止也会调用触发器进程
#example
---
- name: apache change port
hosts: 172.25.0.254
force_handlers: yes
vars:
http_port: 80
tasks:
- name: configure apache conf file
lineinfile:
path: /etc/httpd/conf/httpd.conf
regexp: "^Listen"
line: "Listen {{ http_port }}"
notify: restart apache
- name: install error
dnf:
name: westos
state: latest
handlers:
- name: restart apache
service:
name: httpd
state: restarted
enabled: yes
3.changed_when
#作用:
#控制任务在何时报告它已进行更改;强制更改:true,强制不更改:false
---
- name: apache change port
hosts: 172.25.0.254
force_handlers: yes
vars:
http_port: 8080
tasks:
- name: configure apache conf file
lineinfile:
path: /etc/httpd/conf/httpd.conf
regexp: "^Listen"
line: "Listen {{ http_port }}"
changed_when: true
notify: restart apache
handlers:
- name: restart apache
service:
name: httpd
state: restarted
enabled: yes
4.failed_when
#当符合条件时强制任务失败
#强制某个play为失败状态
---
- name: test
hosts: 172.25.0.254
tasks:
- name: shell
shell: echo hello
register: westos
failed_when: "'hello' in westos.stdout"
5.block
block: ##定义要运行的任务
rescue: ##定义当block句子中出现失败任务后运行的任务
##block运行成功,则rescue不运行
always: ##定义最终独立运行的任务
五、 练习
建立playbook ~/westos.yml要求如下:
建立大小为1500M名为/dev/vdb1的设备
如果/dev/vdb不存在请输入:
/dev/vdb is not exist
如果/dev/vdb大小不足1.5G请输出:
/dev/vdb is less then 1.5G
并建立800M大小的/dev/vdb1
此设备挂载到/westos上
- name: test fdisk
hosts: all
tasks:
- name: check sdb
debug:
msg: /dev/sdb is not exist
when: ansible_facts['devices']['sdb'] is not defined
- name: create /dev/sdb1
block:
- name: check size
parted:
device: /dev/sdb
number: 1
state: present
part_end: 1.5GiB
when: ansible_facts['devices']['sdb'] is defined
- name: show size is not enough 1.5G
debug:
msg: /dev/sdb is not enough 1.5G
rescue:
- name: create /dev/sdb1
parted:
device: /dev/sdb
number: 1
state: present
part_end: 800MiB
notify:
- set filesystem
- mount /dev/sdb1
when: ansible_facts['devices']['sdb'] is defined
always:
- name: create mount point
file:
path: /westos
state: directory
handlers:
- name: set filesystem
filesystem:
fstype: ext4
dev: /dev/sdb1
- name: mount /dev/sdb1
mount:
path: /westos/
src: /dev/sdb1
fstype: ext4
state: mounted