ansible生产环境使用场景(二)

? 生产上新入网的服务器都需要安装prometheus的监控客户端软件，主要步骤有：新建监控用户、拷贝客户端软件、拉起客户端进程、开机自启动。本文记录了使用ansible的role方式批量快速的安装该客户端软件。

? 本文使用到的主要模块：user、stat、copy、shell、script、lineinfile等。

环境说明：

一、创建目录列表

[ ~]# cd /etc/ansible/roles         
[ roles]# ansible-galaxy init prometheus
- Role prometheus was created successfully
[ roles]# tree prometheus
prometheus
├── defaults
│?? └── main.yml
├── files
├── handlers
│?? └── main.yml
├── meta
│?? └── main.yml
├── README.md
├── tasks
│?? └── main.yml
├── templates
├── tests
│?? ├── inventory
│?? └── test.yml
└── vars
    └── main.yml

8 directories, 8 files

使用ansible-galaxy命令初始化role的目录

二、生成密码

1.安装pip3

[ ~]# yum -y install python3-pip

2.安装passlib模块

[ ~]# cd /tmp
[ tmp]# pip3 download passlib==1.7.2 -d /tmp/pkg
[ tmp]# more requirements.txt 
passlib==1.7.2
[ tmp]# pip3 install --no-index --find-links=./pkg -r requirements.txt 
WARNING: Running pip install with root privileges is generally not a good idea. Try `pip3 install --user` instead.
Collecting passlib==1.7.2 (from -r requirements.txt (line 1))
Installing collected packages: passlib
Successfully installed passlib-1.7.2

生产密码会使用到Python的passlib模块

3.生成密码密文

[ ~]# python3 -c "from passlib.hash import sha512_crypt; import getpass; print(sha512_crypt.using(rounds=5000).hash(getpass.getpass()))"
Password: 
$6$irgqm/Fea6/O07B7$LJpYtZoKqUkF.pN4D71LX2Cac3TNrF2.1GKGLfaSWxvKupknNLbWNcYym3LuojT3BqUeUCgsrmD/M6FqTx4lK/

输入明文密码会生成密码密文，复制该密码，后面创建用户时会用到。

三、文件总览

1.执行文件

[ ansible]# pwd
/etc/ansible
[ ansible]# more prometheus.yaml 
---
- hosts: "{{ hostlist }}"
  gather_facts: no
  roles:
  - role: prometheus

2.task文件

[ ~]# cd /etc/ansible/roles
[ roles]# more prometheus/tasks/main.yml 
---
# tasks file for prometheus
# author: loong576

- name: user search
  shell: id {{ user_name }}
  register: user_search
  ignore_errors: true

- name: user add 
  user: 
    name: "{{ user_name }}"
    shell: "{{ user_bash }}"
    password: "{{ user_password }}"
  when: user_search.failed == true

- name: file search
  stat:
    path: "{{ file_dest }}/{{ file_src }}"    
  register: file_search

- name: copy files
  copy:
    src: "{{ file_src }}"
    dest: "{{ file_dest }}"
    mode: 0755
  when: file_search.stat.exists == false

- name: process search
  shell: "ps -ef|grep node_exporter |grep -v grep"
  register: process
  ignore_errors: true

- name: install node_exporter
  environment:
    dest: "{{ file_dest }}"
    src: "{{ file_src }}"
    port: "{{ node_port }}"
  script:
    startup.sh
  register: start
  tags: start
  when: process.failed  == true 

- name: exec when startup
  lineinfile:
    dest: /etc/rc.local
    line: nohup {{ file_dest }}/{{ file_src }} --web.listen-address=:{{ node_port }} >/dev/null &

执行逻辑为：判断被执行主机上有无监控用户，若无则新增；判断被执行主机有无客户端文件，若无则拷贝；判断被执行主机有无客户端进程，若无则拉起；最后设置客户端进程开机自启动。

3.default文件

[ roles]# more prometheus/defaults/main.yml 
---
# defaults file for prometheus
user_name: sysmonitor 
user_bash: /bin/bash
user_password: $6$bB7R8JF3U7L7s/3E$fKOQwpoZ7RESfMmX6uqts1gw4yeXniRNctI2JRBRS2/120EgrHCWS3DboiRhO5sN0CjoVxvtAKgeDVQRaPlc0/

file_src: node_exporter
file_dest: /home/sysmonitor

node_port: 9100

定义监控用户的用户名、shell、密码，客户端执行文件的文件名、文件路径和端口。

4.file文件

[ roles]# ll prometheus/files/
总用量 16512
-rw-r--r-- 1 root root 16900416 7月  30 16:04 node_exporter
-rwxr--r-- 1 root root      102 7月  31 11:32 startup.sh
[ roles]# more prometheus/files/startup.sh 
#/bin/bash
echo $dest
echo $src
echo $port

nohup $dest/$src --web.listen-address=:$port >/dev/null &

file文件有两个，node_exporter为客户端执行文件，startup.sh为客户端进程拉起脚本。

四、运行role

[ ansible]# pwd 
/etc/ansible
[ ansible]# ansible-playbook prometheus.yaml  -e hostlist=test50

‘ -e hostlist=test50’指定被执行的主机为test50，即172.27.34.50

五、运行结果复核

登陆被管主机test50，发现监控用户和监控进程都在且加入到了开机自启动文件中，符合预期。

本文所有脚本和配置文件已上传github：ansible-production-practice-2

更多请点击：ansible系列文章