一、简介
Ansible是一种集IT系统的配置管理、应用部署、流程设置的开源软件工具,与其他管理软件工具有多方面的差异。目标是提供面对广泛的自动化挑战如何获得大型生产力的优势。当Ansible提供更强大的生产力逐步替代其他许多核心性能的自动化解决方案,它也在寻求解决其他还没解决的IT挑战,这些包括如何时复杂多层级工作流程清晰化、清楚统一的OS配置、在单一框架下应用软件的部署。
官方文档:http://docs.ansible.com/#playbooks
二、直接安装配置
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[root@localhost ~] # yum -y install ansible-1.5.4-1.el6.noarch.rpm
#下载安装包后使用yum安装;因为存在依赖关系 # [root@localhost ~] # rpm -ql ansible
/ etc / ansible
/ etc / ansible / ansible.cfg
/ etc / ansible / hosts
/ usr / bin / ansible
/ usr / bin / ansible - doc
/ usr / bin / ansible - galaxy
/ usr / bin / ansible - playbook
/ usr / bin / ansible - pull
/ usr / bin / ansible - vault
/ usr / lib / python2. 6 / site - packages / ansible
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安装完成后进行配置:
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[root@localhost ~] # vim /etc/ansible/hosts
[webserver] #定义一组服务
node1.soul.com node2.soul.com [dbserver] node3.soul.com # #定义完成后进行ssh认证 [root@localhost ~] # ssh-keygen -t rsa
Generating public / private rsa key pair.
Enter file in which to save the key ( / root / .ssh / id_rsa):
Enter passphrase (empty for no passphrase):
[root@localhost ~] # ssh-copy-id -i .ssh/id_rsa.pub node1
[root@localhost ~] # ssh-copy-id -i .ssh/id_rsa.pub node2
[root@localhost ~] # ssh-copy-id -i .ssh/id_rsa.pub node3
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基本语法:
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[root@localhost ~] # man ansible
ANSIBLE( 1 ) System administration commands ANSIBLE( 1 )
NAME ansible - run a command somewhere else
SYNOPSIS ansible <host - pattern> [ - f forks] [ - m module_name] [ - a args]
#host-pattern 主机列表 #-f forks 一次管理多少 #-m module_name 指定模块;默认为command #-a args 参数 # [root@localhost ~] # ansible all -a 'date'
node2.soul.com | success | rc = 0 >>
Sat Apr 19 22 : 28 : 00 CST 2014
node1.soul.com | success | rc = 0 >>
Sat Apr 19 22 : 28 : 00 CST 2014
node3.soul.com | success | rc = 0 >>
Sat Apr 19 22 : 28 : 00 CST 2014
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#显示所有模块 [root@localhost ~] # ansible-doc -l
acl Sets and retrieves file ACL information.
add_host add a host ( and alternatively a group) to the ansible - playbo
airbrake_deployment Notify airbrake about app deployments apt Manages apt - packages
apt_key Add or remove an apt key
apt_repository Add and remove APT repositores
arista_interface Manage physical Ethernet interfaces arista_l2interface Manage layer 2 interfaces
arista_lag Manage port channel (lag) interfaces arista_vlan Manage VLAN resources assemble Assembles a configuration file from fragments
assert Fail with custom message
at Schedule the execution of a command or scripts via the at co
authorized_key Adds or removes an SSH autho
... # [root@localhost ~] # ansible-doc -s
Usage: ansible - doc [options] [module...] #查看模块的参数
[root@localhost ~] # ansible-doc -s yum
- name: Manages packages with the `yum' package manager
action: yum
state = # Whether to install (`present', `latest'), or remove (`absent') a packa
disablerepo = # `repoid' of repositories to disable for the install/update operation T
name = # Package name, or package specifier with version, like `name-1.0'. When
enablerepo = # Repoid of repositories to enable for the install/update operation. The
list = # Various (non-idempotent) commands for usage with `/usr/bin/ansible' an
disable_gpg_check = # Whether to disable the GPG checking of signatures of packages being in
conf_file =
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测试安装包:
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[root@localhost ~] # ansible all -m yum -a "state=present name=corosync"
node2.soul.com | success >> { "changed" : true,
"msg" : "",
"rc" : 0 ,
"results" :
... #由于需要依赖关系;所以会输出很多信息;这里不贴了 [root@localhost ~] # ansible all -a "rpm -q corosync" 验证
node2.soul.com | success | rc = 0 >>
corosync - 1.4 . 1 - 17.el6 .x86_64
node3.soul.com | success | rc = 0 >>
corosync - 1.4 . 1 - 15.el6 .x86_64
node1.soul.com | success | rc = 0 >>
corosync - 1.4 . 1 - 17.el6 .x86_64
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三、YAML语法
YAML的语法和其他高阶语言类似,并且可以简单表达清单、散列表、标量等数据结构。其结构(Structure)通过空格来展示,序列(Sequence)里的项用"-"来代表,Map里的键值对用":"分隔。下面是一个示例。
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name: Tom Smith age: 40
gender: Male spouse: name: Jerry Smith
age: 35
gender: Female
children: - name: Jimmy Smith
age: 17
gender: Male
- name: Jenny Smith
age: 15
gender: Female
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YAML文件扩展名通常为.yaml,如example.yaml。
四、ansible playbooks
playbook是由一个或多个“play”组成的列表。play的主要功能在于将事先归并为一组的主机装扮成事先通过ansible中的task定义好的角色。从根本上来讲,所谓task无非是调用ansible的一个module。将多个play组织在一个playbook中,即可以让它们联同起来按事先编排的机制同唱一台大戏。下面是一个简单示例
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- hosts: webnodes
vars :
http_port: 80
max_clients: 256
remote_user: root
tasks:
- name: ensure apache is at the latest version
yum: name = httpd state = latest
- name: ensure apache is running
service: name = httpd state = started
handlers:
- name: restart apache
service: name = httpd state = restarted
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五、Hosts和Users
playbook中的每一个play的目的都是为了让某个或某些主机以某个指定的用户身份执行任务。hosts用于指定要执行指定任务的主机,其可以是一个或多个由冒号分隔主机组;remote_user则用于指定远程主机上的执行任务的用户。如上面示例中的
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- hosts: webnodes
remote_user: root
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不过,remote_user也可用于各task中。也可以通过指定其通过sudo的方式在远程主机上执行任务,其可用于play全局或某任务;此外,甚至可以在sudo时使用sudo_user指定sudo时切换的用户。
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- hosts: webnodes
remote_user: mageedu
tasks:
- name: test connection
ping:
remote_user: mageedu
sudo: yes
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六、任务列表和action
play的主体部分是task list。task list中的各任务按次序逐个在hosts中指定的所有主机上执行,即在所有主机上完成第一个任务后再开始第二个。在运行自下而下某playbook时,如果中途发生错误,所有已执行任务都将回滚,因此,在更正playbook后重新执行一次即可。
task的目的是使用指定的参数执行模块,而在模块参数中可以使用变量。模块执行是幂等的,这意味着多次执行是安全的,因为其结果均一致。
每个task都应该有其name,用于playbook的执行结果输出,建议其内容尽可能清晰地描述任务执行步骤。如果未提供name,则action的结果将用于输出。
定义task的可以使用“action: module options”或“module: options”的格式,推荐使用后者以实现向后兼容。如果action一行的内容过多,也中使用在行首使用几个空白字符进行换行。
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tasks: - name: make sure apache is running
service: name = httpd state = running
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在众多模块中,只有command和shell模块仅需要给定一个列表而无需使用“key=value”格式,例如:
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tasks: - name: disable selinux
command: / sbin / setenforce 0
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如果命令或脚本的退出码不为零,可以使用如下方式替代:
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tasks: - name: run this command and ignore the result
shell: / usr / bin / somecommand || / bin / true
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或者使用ignore_errors来忽略错误信息:
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tasks: - name: run this command and ignore the result
shell: / usr / bin / somecommand
ignore_errors: True
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七、handlers:用于当关注的资源发生变化时采取一定的操作。
“notify”这个action可用于在每个play的最后被触发,这样可以避免多次有改变发生时每次都执行指定的操作,取而代之,仅在所有的变化发生完成后一次性地执行指定操作。在notify中列出的操作称为handler,也即notify中调用handler中定义的操作。
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- name: template configuration file
template: src = template.j2 dest = / etc / foo.conf
notify:
- restart memcached
- restart apache
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handler是task列表,这些task与前述的task并没有本质上的不同。
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handlers: - name: restart memcached
service: name = memcached state = restarted
- name: restart apache
service: name = apache state = restarted
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实例:
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#安装heartbeat的 heartbeat.yaml - hosts: hbhosts
remote_user: root
tasks:
- name: ensure heartbeat latest version
yum: name = heartbeat state = present
- name: authkeys configure file
copy: src = / root / hb_conf / authkeys dest = / etc / ha.d / authkeys
- name: authkeys mode 600
file : path = / etc / ha.d / authkeys mode = 600
notify:
- restart heartbeat
- name: ha.cf configure file
copy: src = / root / hb_conf / ha.cf dest = / etc / ha.d / ha.cf
notify:
- restart heartbeat
handlers:
- name: restart heartbeat
service: name = heartbeat state = restarted
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本文转自Mr_陈 51CTO博客,原文链接:http://blog.51cto.com/chenpipi/1399808,如需转载请自行联系原作者