Ansible Playbooks
Playbook核心元素
hosts
一个或多个组或主机的 patterns,以逗号为分隔符 。
- hosts: webservices
remote_user: root
Tasks
任务集
tasks:
- name: install httpd
yum: name=httpd
- name: start httpd
service: name=httpd state=started
Handlers 和 notity
由特定条件触发的操作，满足条件方才执行，否则不执行。 Handlers也是task列表，这些task与前述的task并没有本质上的不同,用于当关注的资源发生变化时，才会采取一定的操作。
- hosts: webs
remote_user: root
tasks:
- name: install httpd
yum: name=httpd
- name: change httpd.conf
copy: src=/app/httpd.conf dest=/etc/httpd/conf/ backup=yes
notify: restart httpd > 在 notify 中定义内容一定要和handlers中定义的 - name 内容一样，这样才能达到触发的效果，否则会不生效。
- name: start httpd
service: name=httpd state=started
- name: wall http status
shell: /usr/bin/wall `ss -nltp|grep httpd`
handlers:
- name: restart httpd > 只有接收到通知才会执行这里的任务
service: name=httpd state=restarted
Tags
给指定的任务定义一个调用标识 由于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: webs
remote_user: root
tasks:
- name: install httpd
yum: name=httpd
tags: install
ansible-playbook -t install web.yaml
Variables 变量
- 通过命令行指定变量，优先级最高。
ansible-playbook – variable_name=value
-
facts setup模块就是用来获取远程主机的相关信息的。一般以ansible_ 开头的就是变量可以调用。
-
/etc/ansible/hosts inventory
每台主机单独设置
IP/HOSTNAME variable_name=value
组内统一设置
[groupname:vars]
variable_name=value
还可以使用参数, 用于定义ansible远程连接目标主机时使用的属性，而非传递给playbook的变量。
ansible_ssh_host
ansible_ssh_port
ansible_ssh_user
ansible_ssh_pass
ansible_sudo_pass
- 在playbook中定义
vars:
- var_name: value
- var_name: value
-
register 在有些时候，我们希望把某一条任务执行的结果保存下来，可以在接下的任务中调用或者做些判断，可以通过register关键字来实现。
-
角色调用
-
vars_files指定变量文件
优先级 命令行 -e > vars_files指定变量文件 > 主机清单普通变量 > 主机清单公共(组)变量
- 语法检测
ansible-playbook --syntax-check /path/to/playbook.yaml
-
测试运行
- –list-hosts
- -list-tasks
- –list-tags
ansible-playbook -C /path/to/playbook.yaml
-
执行运行
- -t TAGS, –tags=TAGS
- –skip-tags=SKIP_TAGS
- –start-at-task=START_AT
ansible-playbook /path/to/playbook.yaml
变量示例
cat hosts
[webservers]
10.1.88.72 name=iam72
10.1.88.73 name=iam73
[webservers:vars]
place="host_vars.txt"
cat vars.yaml
- hosts: all
vars:
filename: "abcd.txt"
vars_files:
- vars/test_vars.yml
tasks:
- name: test playbook vars
file: path="/tmp/{{ filename }}" state=touch
tags: playbook_vars
- name: test setup vars
copy: dest=/tmp/a.txt content="{{ ansible_all_ipv4_addresses }}"
tags: setup_vars
- name: test hosts vars
copy: dest="/tmp/{{ place }}" content="{{ name }}"
tags: hosts_vars
- name: test var files
file: path="/tmp/{{ var_file }}" state=touch
tags: file_var
- name: test register var
shell: /bin/cat /etc/centos-release
ignore_errors: true
register: release
tags: register_var
- name: show release
debug: var=release
ansible-playbook vars.yaml --list-tags
playbook: vars.yaml
play #1 (all): all TAGS: []
TASK TAGS: [file_var, hosts_vars, playbook_vars, register_var, setup_vars]
ansible-playbook vars.yaml --list-tasks
playbook: vars.yaml
play #1 (all): all TAGS: []
tasks:
test playbook vars TAGS: [playbook_vars]
test setup vars TAGS: [setup_vars]
test hosts vars TAGS: [hosts_vars]
test var files TAGS: [file_var]
test register var TAGS: [register_var]
show release TAGS: []
ansible-playbook vars.yaml --list-hosts
playbook: vars.yaml
play #1 (all): all TAGS: []
pattern: [u'all']
hosts (2):
10.1.88.73
10.1.88.72
ansible-playbook vars.yaml
PLAY [all] ********************************************************************************************************************************
TASK [Gathering Facts] ********************************************************************************************************************
ok: [10.1.88.72]
ok: [10.1.88.73]
TASK [test playbook vars] ****************************************************************************************************************
changed: [10.1.88.73]
changed: [10.1.88.72]
TASK [test setup vars] ******************************************************************************************************************
changed: [10.1.88.73]
changed: [10.1.88.72]
TASK [test hosts vars] *********************************************************************************************************************
changed: [10.1.88.73]
changed: [10.1.88.72]
TASK [test var files] **********************************************************************************************************************
changed: [10.1.88.72]
changed: [10.1.88.73]
TASK [test register var] ********************************************************************************************************************
changed: [10.1.88.73]
changed: [10.1.88.72]
TASK [show release] **************************************************************************************************************************
ok: [10.1.88.72] => {
"release": {
"changed": true,
"cmd": "/bin/cat /etc/centos-release",
"delta": "0:00:00.027839",
"end": "2018-10-26 13:15:35.752900",
"failed": false,
"rc": 0,
"start": "2018-10-26 13:15:35.725061",
"stderr": "",
"stderr_lines": [],
"stdout": "CentOS Linux release 7.5.1804 (Core) ",
"stdout_lines": [
"CentOS Linux release 7.5.1804 (Core) "
]
}
}
ok: [10.1.88.73] => {
"release": {
"changed": true,
"cmd": "/bin/cat /etc/centos-release",
"delta": "0:00:00.035317",
"end": "2018-10-26 13:15:35.746466",
"failed": false,
"rc": 0,
"start": "2018-10-26 13:15:35.711149",
"stderr": "",
"stderr_lines": [],
"stdout": "CentOS Linux release 7.5.1804 (Core) ",
"stdout_lines": [
"CentOS Linux release 7.5.1804 (Core) "
]
}
}
PLAY RECAP **********************************************************************************************************************************
10.1.88.72 : ok=7 changed=5 unreachable=0 failed=0
10.1.88.73 : ok=7 changed=5 unreachable=0 failed=0
when 条件判断
举例判断当前主机是Centos 6 Or Centos 7
1.利用setup 模块获取系统信息
ansible all -m setup | less
"ansible_distribution": "CentOS",
"ansible_distribution_major_version": "7",
2.利用上面的信息作为判断条件
- hosts: all
tasks:
- name: centos 6 task
shell: echo "i am centeos 6"
when: ansible_distribution == "CentOS" and ansible_distribution_major_version == "6"
- name: centos 7 task
shell: echo "i am centeos 7"
when: ansible_distribution == "CentOS" and ansible_distribution_major_version == "7"
with_items 重复执行
- hosts: all
tasks:
- name: install base packages # 一次安装多个安装包
yum: name={{ item }} state=installed
with_items:
- vim
- git
- wget
- psmisc
- net-tools
- bash-completion
- name: create groups # 字典
group: name={{ item }} state=present
with_items:
- group1
- group2
- name: create users
user: name={{ item.user }} group={{ item.group }} state=present
with_items:
- {user: 'user1' , group: 'group1'}
- {user: 'user2' , group: 'group2'}
templates 模板，文本文件，内部嵌套有模板语言脚本（使用Jinja2模板语言编写）
- 算数运算
.j2
server {
worker_connectios {{ ansible_processor_vcpus *2 }};
}
.yaml
- hosts: nginx
tasks:
- name: generate nginx conf
template: src=templates/nginx.conf.j2 dest=/etc/nginx/nginx.conf
- for 循环
.j2
server {
{% for port in port_list %}
listen port;
{% endfor %}
}
.yaml
- hosts: nginx
vars:
- port_list:
- 443
- 80
- 8080
tasks:
- name:
template: src=templates/nginx.conf.j2 dest=/etc/nginx/nginx.conf
.j2
{% for vhost in vhost_list %}
server {
listen vhost.port;
servername vhost.host;
}
{% endfor %}
.yaml
- hosts: nginx
vars:
vhost_list:
- web:
port: 8080
host: web1
- web:
port: 9090
host: web2
- if 判断
.j2
{% for vhost in vhost_list %}
server {
listen vhost.port;
{% if vhost.host is defined%}
servername vhost.host;
{% endif %}
}
{% endfor %}
.yaml
- hosts: nginx
vars:
vhost_list:
- web:
port: 8080
host: web1
- web:
port: 9090