ansible-playbook模板的简单应用

需求:

多台机器根据硬件指标来设置nginx的worker_processes,并为nginx设置不同的端口.

实现步骤

1. 在不知道cpu变量名称的情况下,使用ansible的setup模块来获取cpu的变量名称

[root@localhost playbook]# ansible all -m setup | grep cpu
        "ansible_processor_vcpus": 2,
        "ansible_processor_vcpus": 2,

2. 为每台机器设置不同的端口号:

[node]
192.168.0.107 hostname=node1 port=80
192.168.0.108 hostname=node2 port=81

3. 创建templates目录并设置nginx配置文件模板,模板名称后缀为.j2 :

mkdir templates
cp /etc/nginx/nginx.conf  ./templates/nginx.conf.j2

4. 修改nginx模板:

[root@localhost playbook]# cat templates/nginx.conf.j2
# For more information on configuration, see:
#   * Official English Documentation: http://nginx.org/en/docs/
#   * Official Russian Documentation: http://nginx.org/ru/docs/

user nginx;
worker_processes {{ ansible_processor_vcpus*2 }}; #此处使用cpu数量的2倍
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
 server {
       # 为每台机器指定nginx端口
        listen       {{ port }}  default_server;
        listen       [::]:{{ port }} default_server;   

5. 创建nginx服务的yaml文件:

[root@localhost playbook]# cat nginx.yaml
---
- hosts: all
  remote_user: root
  vars:
    - pkg1: nginx
    - port: 88

  tasks:
    - name: install {{ pkg1 }}
      yum: name=nginx
    - name: close httpd
      service: name=httpd state=stopped
    - name: copy {{ pkg1 }} config file
      template: src=nginx.conf.j2 dest=/etc/nginx/nginx.conf
      notify:
        - restartsrv
    - name: start {{ pkg1 }} server
      service: name=nginx state=started enabled=yes

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

6. nginx.yaml文件语法检查:

[root@localhost playbook]# ansible-playbook nginx.yaml -C

7. 运行

[root@localhost playbook]# ansible-playbook nginx.yaml

8.验证

[root@localhost playbook]# ansible node -m shell -a 'ss -ntpl | grep nginx'
192.168.0.108 | CHANGED | rc=0 >>
LISTEN     0      128          *:81                       *:*                   users:(("nginx",pid=2963,fd=6),("nginx",pid=2962,fd=6),("nginx",pid=2961,fd=6),("nginx",pid=2960,fd=6),("nginx",pid=2959,fd=6))
LISTEN     0      128         :::81                      :::*                   users:(("nginx",pid=2963,fd=7),("nginx",pid=2962,fd=7),("nginx",pid=2961,fd=7),("nginx",pid=2960,fd=7),("nginx",pid=2959,fd=7))
192.168.0.107 | CHANGED | rc=0 >>
LISTEN     0      128          *:80                       *:*                   users:(("nginx",pid=7775,fd=6),("nginx",pid=7774,fd=6),("nginx",pid=7773,fd=6),("nginx",pid=7772,fd=6),("nginx",pid=7771,fd=6))
LISTEN     0      128         :::80                      :::*                   users:(("nginx",pid=7775,fd=7),("nginx",pid=7774,fd=7),("nginx",pid=7773,fd=7),("nginx",pid=7772,fd=7),("nginx",pid=7771,fd=7))
``