Ansible it!

• 一、简介
• 二、运行环境
  • 配置文件
• 三、帮助工具
• 四、组件介绍
  • (1)inventory
  • (2)Ah-Hoc命令
  • (3)Playbook
• 五、Playbook
  • (1)基本语法
  • (2)变量与引用
  • (3)循环
  • (4)lookups
  • (5)conditionals
  • (6)Jinja2 filter
  • (7)内置变量

一、简介

在进行多个服务器配置管理时，为了提高效率，通过ansible达到同时管理所有节点，ansible基于python编写，由Paramiko和PyYAML俩个关键模块构建

特点如下：

• 没有客户端，通过ssh链接节点
• 不仅仅支持python，还支持多种动态语言开发模块
• 非root账户也可使用
• 轻量级
• 简单易读
• … …

二、运行环境

配置文件

查找配置文件的顺序

1. 环境变量
2. ./ansible.cfg
3. ~/.ansible.cfg
4. /etc/ansible/ansible.cfg

ansible.cfg参数列表如下

• inventory 主机列表 /etc/ansible/hosts
• library 存放模块的目录 /usr/share/my_modules/
• forks 最多多少个进程同时工作 5
• sudo_user 默认执行命令的用户 root
• remote_port 远程端口 22
• host_key_checking 是否检查主机秘钥,一般下发控制主机的ssh公钥到节点，从而使用无密码访问 false
• timeout 超时间隔 10
• log_path 日志路径，默认不记录，只有指定路径才记录 /var/log/ansible.log
• … …

三、帮助工具

# 显示所有模块
ansible-doc -l
# 显示该模块用法
ansible-doc ping

四、组件介绍

inventory

静态主机配置列表

/etc/ansible/hosts

172.29.88.100
172.29.88.103 ansible_ssh_pass='123456'
[buildnodes]
172.29.88.100
172.29.88.133
[buildnodes:vars]
ansible_ssh_pass='123456'
[allnodes:children]
buildnodes
172.29.88.156

当然，可以在ansible.cfg中指定inventory为目录，这样该目录下的文件都是可以做主机配置列表

动态主机配置列表

在执行ansible命令时，使用-i参数指定该脚本即可，该脚本必须支持–list(-l)和–host(-H) + 主机ip，前者是返回所有主机及主机组信息，后者返回该主机的变量信息，返回格式都是json格式

一个参考的脚本

#!/usr/bin/env python3
#coding:utf8
import json
import sys
 
def all():
    info_dict = {
    "all":[
        "10.10.0.109",
        "10.10.0.112"]
    }
    print(json.dumps(info_dict,indent=4))
 
def group():
    host1 = ['10.10.0.112']
    host2 = ['10.10.0.112','10.10.0.109']
    group1 = 'test1'
    group2 = 'test2'
    hostdata = {
        group1:{"hosts":host1},
        group2:{"hosts":host2}
    }
    print(json.dumps(hostdata,indent=4))
 
def host(ip):
    info_dict = {
        "10.10.0.112": {
            "ansible_ssh_host":"10.10.0.112",
            "ansible_ssh_port":22,
            "ansible_ssh_user":"root",
            "ansible_ssh_pass":"123457"
        },
        "10.10.0.109": {
            "ansible_ssh_host":"10.10.0.109",
            "ansible_ssh_port":22,
            "ansible_ssh_user":"root",
            "ansible_ssh_pass":"xxxx"
        }
    }
    print(json.dumps(info_dict,indent=4))
 
if len(sys.argv) == 2 and (sys.argv[1] == '--list'):
    group()
elif len(sys.argv) == 3 and (sys.argv[1] == '--host'):
    host(sys.argv[2])
else:
    print("Usage: %s --list or --host <hostname>" % sys.argv[0])
    sys.exit(1)

内置参数

ansible_ssh_user

ansible_ssh_pass

ansible_python_interpreter

ansible_shell_type

Ah-Hoc命令

1.后台运行

# 后台执行最大时间是120秒，每1秒检查一下状态
ansible buildnodes -m shell -a 'sleep 5;cat /etc/issue' -P 1 -B 120 -f 2 -o

2.复制文件

ansible buildnodes -m copy 'src=hosts.py dest=/root/hosts.py owner=root group=root mode=644 backup=yes' -o

3.包管理

ansible buildnodes -m apt -a 'name=sysstat state=latest' -f 2 -o

4.用户管理

ansible buildnodes -m user -a 'name=tester password="$1$s3aRAhUo$B8S/ei.VeKLJSC3h37aMP1"'

Playbook

facts组件

ansible buildnodes -m setup
ansible buildnodes -m setup -a 'filter="ansible_python_version"'

五、Playbook

基本语法

---
- hosts: all
    tasks:
        - name: Install Nginx Package
          apt: name=nginx state=present

        - name: Copy Nginx.conf
          template: src=./nginx.conf.j2 dest=/etc/nginx/nginx.conf owner=root group=root mode=0644 validate='nginx -t -c %s'
          notify:
            - ReStart Nginx Service

    handlers:
        - name: ReStart Nginx Service
          service: name=nginx state=restarted

# 进行语法检查
ansible-playbook nginx.yaml --syntax-check
# 列出所有task
ansible-playbook nginx.yaml --list-task
# 部署
ansible-playbook -i hosts nginx.yaml -f 3

变量与引用

---
  - hosts: all
    gather_facts: False
    vars_prompt:        #执行playbook时交互输入
      - name: "one"
        prompt: "first"
        default: "ok"
        private: no
    vars:               #定义变量
      xixi: gege
    vars_files:         #从文件中获取变量
      - var.json
    tasks:
      - name: display host info
        debug: msg="the {{ inventory_hostname }} user is {{  ansible_ssh_user }},{{ hehe }},{{ xixi}},{{one}} "
      - name: register variable
        shell: hostname
        register: info
      - name: display variable
        debug: msg="The variable is {{ info }} " #info是python字典，info['stdout']是执行的结果

# 在执行playbook时指定变量
ansible-playbook playbook.yaml -e "hehe=bilibili"
ansible-playbook playbook.yaml -e "@var.json"

循环

1.标准loops

---
    - hosts: all
      gather_facts: False
      tasks:
          - name: debug loops
            debug: msg="name -> {{ item.key }},value -> {{ item.value }} "
            with_items:
              - {key: "one",value: "hehe"}
              - {key: "second",value: "haha"}

2.嵌套loops

---
    - hosts: all
      gather_facts: False
      tasks:
          - name: debug loops
            debug: msg="name -> {{ item[0] }},value -> {{ item[1] }}"
            with_nested:
            - ['A']
            - ['a','b','c']

3.散列loops

---
    - hosts: buildnodes
      gather_facts: False
      vars:
          users:
              jenkins:
                  name: jenkins
                  shell: bash
              root:
                  name: root
                  shell: sh
      tasks:
          - name: debug loops
            debug: msg="name -> {{ item.key }},value -> {{ item.value.name }} shell -> {{ item.value.shell }}"
            with_dict: users

4.文件匹配loops

---
    - hosts: buildnodes
      gather_facts: False
      tasks:
          - name: debug loops
            debug: msg="files -> {{ item }}"
            with_fileglob:
                - /roor/ansible/*.yaml

5.随机选择loops

---
    - hosts: buildnodes
      gather_facts: False
      tasks:
          - name: debug loops
            debug: msg="name -> {{ item }}"
            with_random_choice:
                - "1"
                - "2"
                - "3"

6.条件判断loops

---
    - hosts: buildnodes
      gather_facts: False
      tasks:
          - name: debug loops
            shell: cat /etc/issue
            register: issue
            until: issue.stdout.startswith("Ubuntu")
            retries: 5
            delay: 5

7.文件优先匹配loops

---
    - hosts: buildnodes
      gather_facts: False
      tasks:
          - name: debug loops
            debug: msg="files -> {{ item }}"
            with_first_found:
                - "{{ ansible_distribution }}.yaml"
                - "default.yaml"

8.register loops

---
    - hosts: buildnodes
      gather_facts: False
      tasks:
          - name: debug loops
            shell: "{{ item }}"
            with_items:
                - hostname
                - uname
            register: ret
          - name: display loops
            debug: msg="{% for i in ret.results %} {{ i.stdout }} {% endfor %}"

lookups

ansible支持从外部获取数据，lookups就是这样那个一种插件

1.file

---
    - hosts: buildnodes
      gather_facts: False
      vars:
          contents: "{{ lookup('file','/etc/networks') }}"
      tasks:
          - name: debug lookup
            debug: msg="the contents is {% for i in contents.split('\n') %}{{ i }}{% endfor %}"

2.password

---
    - hosts: buildnodes
      gather_facts: False
      vars:
          contents: "{{ lookup('password','hehe') }}"
      tasks:
          - name: debug lookup
            debug: msg="the contents is {{ contents }}"

3.pipe

实际上就是利用python的subprocess.Popen执行shell命令

---
    - hosts: buildnodes
      gather_facts: False
      vars:
          contents: "{{ lookup('pipe','date +%F-%H-%M-%S') }}"
      tasks:
          - name: debug lookup
            debug: msg="the contents is {{ contents }}"

4.redisi_kv

---
    - hosts: buildnodes
      gather_facts: False
      vars:
          contents: "{{ lookup('redis_kv','redis://localhost:6379,ansible') }}"
      tasks:
          - name: debug lookup
            debug: msg="the contents is {% for i in contents.split('\n') %}{{ i }}{% endfor %}"

5.template

---
    - hosts: buildnodes
      gather_facts: True
      vars:
          contents: "{{ lookup('template','./lookups.j2') }}" #lookups.j2是一个jinja模板文件
      tasks:
          - name: debug lookup
            debug: msg="the contents is {% for i in contents.split('\n') %}{{ i }}{% endfor %}"

conditionals

---
    - hosts: buildnodes
      gather_facts: True
      vars:
          contents: "{{ lookup('pipe','date +%F-%H-%M-%S') }}"
      tasks:
          - name: debug lookup
            debug: msg="the contents is {{ contents }}"
            when: ansible_default_ipv4.address == "172.29.88.100"

Jinja2 filter

内置变量

1.groups是inventory中所有主机的信息，是一个json字符串

{'ungrouped': [], 'all': [u'172.29.88.100', u'172.29.88.133', u'172.29.88.156'], u'buildnodes': [u'172.29.88.100', u'172.29.88.133', u'172.29.88.156']}

2.hostvars

3.inventory_hostname是返回inventory文件中定义的主机名，inventory_hostname_short返回的是inventory中定义的主机名的第一部分

4.play_hosts返回当前playbook运行的主机信息，inventory_dir返回当前playbook使用inventory目录