Ansible
SSH-based configuration management, deployment, and task execution system
运维工具的分类:
agent:基于专用的agent程序完成管理功能,puppet, func, zabbix, …
agentless:基于ssh服务完成管理,ansible, fabric, …
架构:
Ansible Core
Modules:
Core Modules
Customed Modules
Host Iventory
Files
CMDB
PlayBooks
Hosts
roles
Connection Plugins:
特性:
模块化:调用特定的模块,完成特定的任务;
基于Python语言研发,由Paramiko, PyYAML和Jinja2三个核心库实现
部署简单:agentless;
支持自定义模块,使用任意编程语言
强大的playbook机制
幂等性
安装及程序环境:
程序:
ansible
ansible-playbook
ansible-doc
配置文件:
/etc/ansible/ansible.cfg
主机清单:
/etc/ansible/hosts
插件目录:
/usr/share/ansible_plugins/
基本使用:
ansible命令:
Usage: ansible <host-pattern> [options]
常用选项:
-m MOD_NAME -a MOD_ARGS
配置Host Inventory:
/etc/ansible/hosts
[group_id]
HOST_PATTERN1
HOST_PATTERN2
模块:
获取模块列表:ansible-doc -l
获取指定模块的使用帮助:ansible-doc -s MOD_NAME
常用模块:
ping:探测目标主机是否存活
ansible all -m ping
command:在远程主机执行命令;
ansible all -m commond -a "ifconfig"
commond模块:不能理解管道命令,要调用shell模块来执行
ansible all -m commond -a "echo 'gmtest' | passwd –stdin centos"
shell:在远程主机上调用shell解释器运行命令,支持shell的各种功能,例如管道等
ansible all -m shell -a "echo 'gmtest' | passwd –stdin centos"
注意:command和shell模块的核心参数直接为命令本身;而其它模块的参数通常为“key=value”格式
copy:Copies files to remote locations.
用法:
(1) 复制文件
-a "src= dest= "
(2) 给定内容生成文件
-a "content= dest= "
dest中不指文件名,默认随机生成文件名
其它参数:mode, owner, group, …
ansible all -m copy -a "src=/etc/fstab dest=/tmp/test.gm mode =640"
ansible all -m copy -a "content='hello\nworld\n' dest=/tmp/test.gm mode =640"
file:Sets attributes of files
用法:
(1) 创建目录:
-a "path= state=directory"
(2) 创建链接文件:
-a "path= src= state=link"
(3) 删除文件:
-a "path= state=absent“
ansible all -m file -a "path=/tmp/gm state=directory"
ansible all -m file -a "path=/tmp/gm state=absent"
ansible all -m file -a "path=/tmp/gm src=/etc/fstab state=link"
fetch:Fetches a file from remote nodes
从远端主机获取文件,也可以使用scp命令实现
cron:Manage cron.d and crontab entries
在远端主机上设置周期性任务
-a ""
minute=
hour=
day=
month=
weekday=
job=
name=
user=
state={present|absent}
state=absent+name="STRING":用于取消此任务计划
ansible all -mrcont cron -a "minute='*/5' job='/usr/sbin/ntpdate 10.1.0.1 &>/dev/null' name='sync time'"
ansible all -m cront -a "name='sync time' state='absent'"
hostname:Manage hostname
name=XXX
yum:Manages packages with the I(yum) package manager
-a ""
(1) name= state={present|latest}
(2) name= state=absent
ansible all -m yum "name=httpd"
ansible all -m yum "name=httpd state=absent"
service:Manage services.
-a ""
name=
state=
started
stopped
restarted
reloaded
enabled= on|true
是否开机自启动
runlevel=
ansible websrvs -m yum -a "name=httpd "
ansible websrvs -m service -a "name=httpd state=start enaled=true"
ansible websrvs -m service -a "name=httpd state=started"
script:Runs a local script on a remote node after transferring it
在远端主机上运行一个本地的shell脚本
-a ""
creates # 一个文件名,当这个文件存在,则该命令不执行
free_form= # 本地脚本路径
removes # 一个文件名,这个文件不存在,则该命令不执行
ansible test -m script -a ‘/root/local.sh’
主控端/root/下必须有local.sh脚本
group: Add or remove groups
-a ""
name=
state= # Whether the group should be present or not on the remote host
system=
gid=
ansible all -m group -a "name=gm state=present system=fails gid=2000"
user:Manage user accounts
-a ""
name=
group=
groups=
comment=
uid=
system=
shell=
expires=
home=
ansible all -m user -a "name=gm group=gm groups=tom uid=2000"
setup:Gathers facts about remote hosts
获取远端主机关于ansible的变量
ansible 10.1.0.68 -m setup
YAML:
YAML is a data serialization format designed for human readability and interaction with scripting languages.
数据结构:
key:value
– item1
– item2
– item3
{name:jerry, age:21}
PlayBook:
核心元素:
Tasks:任务,由模块定义的操作的列表
Variables:变量
Templates:模板,即使用了模板语法的文本文件
Handlers:由特定条件触发的Tasks
Roles:角色
playbook的基础组件:
Hosts:运行指定任务的目标主机
remote_user:在远程主机以哪个用户身份执行
sudo_user:非管理员需要拥有sudo权限
tasks:任务列表
模块,模块参数:
格式:
(1) action: module arguments
(2) module: arguments
示例1:<一下内容写入一个.yaml的文件中即可>
- hosts: all remote_user: root tasks: - name: install a group group: name=mygrp system=true - name: install a user user: name=user1 group=mygrp system=true - hosts: websrvs remote_user: root tasks: - name: install httpd package yum: name=httpd - name: start httpd service service: name=httpd state=started - hosts: all remote_user: root tasks: - name: create group group: name=hlr gid=3000 state=presend - name: create user user: name=hlr uid=2500 group=hlr
运行playbook,使用ansible-playbook命令
(1) 检测语法
ansible-playbook –syntax-check /path/to/playbook.yaml
(2) 测试运行
ansible-playbook -C /path/to/playbook.yaml
–list-hosts
–list-tasks
–list-tags
(3) 运行
ansible-playbook /path/to/playbook.yaml
-t TAGS, –tags=TAGS :只运行某个标记的tasks
–skip-tags=SKIP_TAGS
–start-at-task=START_AT
handlers:由特定条件触发的Tasks;
调用及定义方式:
tasks:
– name: TASK_NAME
module: arguments
notify: HANDLER_NAME
handlers:
– name: HANDLER_NAME
module: arguments
示例2:
- hosts: websrvs remote_user: root tasks: - name: install httpd package yum: name=httpd state=latest - name: install conf file copy: src=/root/httpd.conf dest=/etc/httpd/conf/httpd.conf notify: restart httpd service - name: start httpd service service: name=httpd state=started handlers: - name: restart httpd service service: name=httpd state=restarted
tags:给指定的任务定义一个调用标识
– name: NAME
module: arguments
tags: TAG_ID
示例3:
- hosts: websrvs remote_user: root tasks: - name: install httpd package yum: name=httpd - name: create httpd-conf file copy: src=/etc/httpd/conf/httpd.conf dest=/etc/httpd/conf/httpd.conf tags: file_change notify: reload httpd server - name: create httpd index.html file copy: src=/var/www/html/index.html dest=/var/www/html/index.html tags: file_change notify: reload httpd server - name: start httpd server service: name=httpd state=started enabled=on handlers: - name: reload httpd server shell: service httpd restart ansible-playbook -t file_change web.yaml -t TAG_ID1,TAG_ID2可以一次调用多个标签Variables:
类型:
内建:
(1) facts
自定义:
(1) 命令行传递
-e VAR=VALUE
示例4:
- hosts: websrvs remote_user: root tasks: - name: remove a server package yum: name={{ pkgname }} state=absent 使用:ansible-playbook -e pkgname=vsftpd XXX.yaml(2) 在hosts Inventory中为每个主机定义专用变量值
(a) 向不同的主机传递不同的变量
IP/HOSTNAME variable_name=value
示例5:
/etc/ansible/hosts文件中定义 [websrvs] 10.1.43.2 pkgname=httpd 10.1.43.3 pkgname=nginx 脚本中: - hosts: websrvs remote_user: root vars: - name: remove a server package yum: name={{ pkgname }} state=absent(b) 向组内的所有主机传递相同的变量
[groupname:vars]
variable_name=value
示例6:
/etc/ansible/hosts文件中定义 [websrvs] 10.1.43.2 10.1.43.3 [websrvs:vars] pkgname=vsftpd 脚本中: - hosts: websrvs remote_user: root vars: - name: remove a server package yum: name={{ pkgname }} state=absent(3) 在playbook中定义<添加在remote_user后面,tasks前面>
vars:
– var_name: value
– var_name: value
示例7:
- hosts: websrvs remote_user: root vars: - pkgname: vsftpd tasks: - name: remove a server package yum: name={{ pkgname }} state=absent 注意:对此配置文件而言,或命令行以-e给出了变量名的值,命令行的优先级更高(4) Inventory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
…
(5) 在角色调用时传递
roles:
– { role: ROLE_NAME, var: value, …}
变量调用:
{{ var_name }}
Templates:模板
文本文件,内部嵌套有模板语言脚本(使用模板语言编写)
Jinja2 is a template engine written in pure Python. It provides a Django inspired non-XML syntax but supports inline expressions and an optional sandboxed environment.
语法:
字面量:
字符串:使用单引号或双引号;
数字:整数、浮点数;
列表:[item1, item2, …]
元组:(item1, item2, …)
字典:{key1:value1, key2:value2, …}
布尔型:true/false
算术运算:
+, -, *, /, //, %, **
比较操作:
==, !=, >, <, >=, <=
逻辑运算:and, or, not
执行模板文件中的脚本,并生成结果数据流,需要使用template模块;
template:
-a ""
src=
dest=
mode=
onwer=
group=
注意:此模板不能在命令行使用,而只能用于playbook
示例8:
/root/nginx.conf.j2文件: worker_processes {{ ansible_processor_vcpus }}; ansible_processor_vcpus:此参数可以使用ansible IP -m setup 获取 脚本 - hosts: ngxsrvs remote_user: root tasks: - name: install nginx package yum: name=nginx state=latest - name: install conf file template: src=/root/nginx.conf.j2 dest=/etc/nginx/nginx.conf tags: ngxconf notify: reload nginx service - nyuame: start nginx service service: name=nginx state=started enabled=true handlers: - name: reload nginx service shell: /usr/sbin/nginx -s reload
条件测试:
when语句:在tasks中使用,Jinja2的语法格式
示例9:
- hosts: all remote_user: root tasks: - name: install nginx package yum: name=nginx state=latest - name: start nginx service on CentOS6 shell: service nginx start when: ansible_distribution == "CentOS" and ansible_distribution_major_version == "6" - name: start nginx service shell: systemctl start nginx.service when: ansible_distribution == "CentOS" and ansible_distribution_major_version == "7" - hosts: mysqlsrvs remote_user: root tasks: - name: install DB package yum: name=mysql-server when: ansible_distribution == 'CentOS' and ansible_distribution_major_version == '6' - name: install DB package yum: name=mariadb-server when: ansible_distribution == 'CentOS' and ansible_distribution_major_version == '7' - name: start DB service service: name=mysqld state=started enabled=on when: ansible_distribution == 'CentOS' and ansible_distribution_major_version == '6' - name: start DB service service: name=mariadb state=started enabled=on when: ansible_distribution == 'CentOS' and ansible_distribution_major_version == '7'
循环:迭代,需要重复执行的任务;
对迭代项的引用,固定变量名为"item”,使用with_item属性给定要迭代的元素;
元素:列表
字符串
字典
基于字符串列表给出元素示例10:
- hosts: websrvs remote_user: root tasks: - name: install packages yum: name={{ item }} state=latest with_items: - httpd - php - php-mysql - php-mbstring - php-gd
基于字典列表给元素示例11:
- hosts: all remote_user: root tasks: - name: create groups group: name={{ item }} state=present with_items: - groupx1 - groupx2 - groupx3 - name: create users user: name={{ item.name }} group={{ item.group }} state=present with_items: - {name: 'userx1', group: 'groupx1'} - {name: 'userx2', group: 'groupx2'} - {name: 'userx3', group: 'groupx3'}
角色:roles
以特定的层级目录结构进行组织的tasks、variables、handlers、templates、files等
role_name/
files/:存储由copy或script等模块调用的文件
tasks/:此目录中至少应该有一个名为main.yml的文件,用于定义各task;其它的文件需要由main.yml进行“包含”调用
handlers/:此目录中至少应该有一个名为main.yml的文件,用于定义各handler;其它的文件需要由main.yml进行“包含”调用
vars/:此目录中至少应该有一个名为main.yml的文件,用于定义各variable;其它的文件需要由main.yml进行“包含”调用
templates/:存储由template模块调用的模板文本
meta/:此目录中至少应该有一个名为main.yml的文件,定义当前角色的特殊设定及其依赖关系;其它的文件需要由main.yml进行“包含”调用
default/:此目录中至少应该有一个名为main.yml的文件,用于设定默认变量
在playbook中调用角色的方法:
- hosts: HOSTS remote_user: USERNAME roles: - ROLE1 - ROLE2 - { role: ROLE3, VARIABLE: VALUE, ...} - { role: ROLE4, when: CONDITION }
原创文章,作者:megedugao,如若转载,请注明出处:http://www.178linux.com/58276