Ansible playbook 编程

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Ansible playbook 编程

添加用户账号

说明:

1、 运维人员使用的登录账号;

2、 所有的业务都放在 /app/ 下「yun用户的家目录」,避免业务数据乱放;

3、 该用户也被 ansible 使用,因为几乎所有的生产环境都是禁止 root 远程登录的(因此该 yun 用户也进行了 sudo 提权)。

1 # 使用一个专门的用户,避免直接使用root用户
2 # 添加用户、指定家目录并指定用户密码
3 # sudo提权
4 # 让其它普通用户可以进入该目录查看信息
5 useradd -u 1050 -d /app yun && echo \'123456\' | /usr/bin/passwd --stdin yun
6 echo "yun  ALL=(ALL)       NOPASSWD: ALL" >>  /etc/sudoers
7 chmod 755 /app/

Ansible 配置清单Inventory

之后文章都是如下主机配置清单

 1 [yun@ansi-manager ansible_info]$ pwd
 2 /app/ansible_info
 3 [yun@ansi-manager ansible_info]$ cat hosts_key 
 4 # 方式1、主机   端口   密钥
 5 [manageservers]
 6 172.16.1.180:22
 7 
 8 [proxyservers]
 9 172.16.1.18[1:2]:22
10 
11 # 方式2:别名   主机   端口   密码
12 [webservers]
13 web01 ansible_ssh_host=172.16.1.183 ansible_ssh_port=22
14 web02 ansible_ssh_host=172.16.1.184 ansible_ssh_port=22
15 web03 ansible_ssh_host=172.16.1.185 ansible_ssh_port=22

条件判断-when

when 判断在 ansible 任务中的使用频率非常高。

例如判断主机是否已经安装指定的软件包;对机器的操作系统进行判断然后再根据不同的方法「yum或apt等」进行软件包安装;根据操作系统的版本判断进行软件包的安装「是安装MySQL还是Mariadb」等。

示例:根据主机名的不同,下载不同的文件

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 4
 5 -rw-rw-r-- 1 yun yun 950 Oct 26 10:22 test_when.yml
 6 [yun@ansi-manager object04]$ cat test_when.yml 
 7 ---
 8 # 根据 hostname 的不同下载不同的图片
 9 # 特殊组 all,对所有机器有效
10 - hosts: all
11 
12   tasks:
13     - name: "download picture jvm-01-01.png"
14       get_url:
15         url: http://www.zhangblog.com/uploads/jvm/jvm-01-01.png
16         dest: /tmp/
17       when: ansible_hostname == "ansi-haproxy01"
18 
19     - name: "download picture jvm-01-02.png"
20       get_url:
21         url: http://www.zhangblog.com/uploads/jvm/jvm-01-02.png
22         dest: /tmp/
23       when: ansible_hostname == "ansi-haproxy02"
24 
25     - name: "other download picture jvm-01-03.png"
26       get_url:
27         url: http://www.zhangblog.com/uploads/jvm/jvm-01-03.png
28         dest: /tmp/
29       # 从 facts 中获取的变量,ansible_facts[\'ansible_hostname\'] != "ansi-haproxy01" 错误写法;ansible_hostname != "ansi-haproxy01" 正确写法
30       #when: (ansible_hostname != "ansi-haproxy01") and (ansible_hostname != "ansi-haproxy02")  # 写法一
31       #或者如下3行  列表之间关系是 (and 与)  等同于上一行
32       #when:
33       #  - ansible_hostname != "ansi-haproxy01"
34       #  - ansible_hostname != "ansi-haproxy02"
35       #when: ansible_hostname is not match "ansi-haproxy0*"   # 写法二
36       when: (ansible_hostname is match "ansi-manager") or (ansible_hostname is match "ansi-web*")  # 写法三
37 
38 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_when.yml  # 语法检测
39 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_when.yml  # 预执行,测试执行
40 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_when.yml  # 执行
41 
42 PLAY [all] *******************************************************************************************************
43 
44 TASK [Gathering Facts] *******************************************************************************************
45 ok: [web01]
46 ok: [web02]
47 ok: [web03]
48 ok: [172.16.1.180]
49 ok: [172.16.1.181]
50 ok: [172.16.1.182]
51 
52 TASK [download picture jvm-01-01.png] ****************************************************************************
53 skipping: [172.16.1.180]
54 skipping: [web01]
55 skipping: [web02]
56 skipping: [web03]
57 skipping: [172.16.1.182]
58 changed: [172.16.1.181]
59 
60 TASK [download picture jvm-01-02.png] ****************************************************************************
61 skipping: [172.16.1.180]
62 skipping: [web01]
63 skipping: [web02]
64 skipping: [web03]
65 skipping: [172.16.1.181]
66 changed: [172.16.1.182]
67 
68 TASK [other download picture jvm-01-03.png] **********************************************************************
69 skipping: [172.16.1.181]
70 skipping: [172.16.1.182]
71 changed: [web02]
72 changed: [web01]
73 changed: [172.16.1.180]
74 changed: [web03]
75 
76 PLAY RECAP *******************************************************************************************************
77 172.16.1.180               : ok=2    changed=1    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0
78 172.16.1.181               : ok=2    changed=1    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0
79 172.16.1.182               : ok=2    changed=1    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0
80 web01                      : ok=2    changed=1    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0
81 web02                      : ok=2    changed=1    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0
82 web03                      : ok=2    changed=1    unreachable=0    failed=0    skipped=2    rescued=0    ignored=0

标准循环

注意:

1、循环语法有两种:loop 和 with_。

2、loop 是在ansible 2.5 添加的,with_ 是一直存在的,推荐使用 loop。在未来 with_ 可能被弃用。

简单列表循环

如果我们需要在 playbook 中启动多个服务,或者下载多个文件;按照之前所学的,那么我们需要写多个 task。但这样会使得 playbook 变得臃肿,因此这时我们就需要引进循环了。

示例:一次启动多个服务,下载多个文件

使用 loop 方式【推荐】

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 20
 5 -rw-rw-r-- 1 yun yun 594 Aug 23 22:10 test_loop.yml
 6 [yun@ansi-manager object04]$ cat test_loop.yml 
 7 ---
 8 # 启动多个服务 和下载多个文件
 9 - hosts: proxyservers
10 
11   tasks:
12     - name: "start httpd, rpcbind, network server"
13       service:
14         name: "{{ item }}"  # 需要用引号引起来
15         state: started
16       loop:
17         - httpd
18         - rpcbind
19         - network
20 
21     - name: "download multiple file"
22       get_url:
23         url: "{{ item }}"  # 需要用引号引起来
24         dest: /tmp/
25       loop:
26         - http://www.zhangblog.com/uploads/jvm/jvm-01-01.png
27         - http://www.zhangblog.com/uploads/jvm/jvm-01-02.png
28         - http://www.zhangblog.com/uploads/jvm/jvm-01-03.png
29 
30 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_loop.yml  # 语法检测
31 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_loop.yml  # 预执行,测试执行
32 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_loop.yml  # 执行

备注:以上方法可用在 yum 模块中。

使用 with_items 方式

其中 playbook 文件中仅把 loop 变为了 with_items。

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 20
 5 -rw-rw-r-- 1 yun yun 594 Aug 23 22:10 test_with_items.yml
 6 [yun@ansi-manager object04]$ cat test_with_items.yml 
 7 ---
 8 # 启动多个服务 和下载多个文件
 9 - hosts: proxyservers
10 
11   tasks:
12     - name: "start httpd, rpcbind, network server"
13       service:
14         name: "{{ item }}"  # 需要用引号引起来
15         state: started
16       with_items:
17         - httpd
18         - rpcbind
19         - network
20 
21     - name: "download multiple file"
22       get_url:
23         url: "{{ item }}"  # 需要用引号引起来
24         dest: /tmp/
25       with_items:
26         - http://www.zhangblog.com/uploads/jvm/jvm-01-01.png
27         - http://www.zhangblog.com/uploads/jvm/jvm-01-02.png
28         - http://www.zhangblog.com/uploads/jvm/jvm-01-03.png
29 
30 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_with_items.yml  # 语法检测
31 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_with_items.yml  # 预执行,测试执行
32 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_with_items.yml  # 执行

如果用在 yum 模块中则会报如下弃用告警,因此该方法不适用于 yum 模块。

Ansible playbook 编程

遍历哈希列表

如果我们需要创建多个用户并且每个用户都有指定的附加组;或者要创建多个文件,每个文件属主、属组、权限不一样;或者需要拷贝文件,但是每个文件的位置不一样,且属主、属组、权限不一样等等;那之前所学的简单循环就不能满足我们的需求了。这时「哈希列表循环」就闪亮登场了。

示例:

使用 loop 方式【推荐】

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 16
 5 drwxrwxr-x 2 yun yun   56 Oct 26 16:03 file
 6 -rw-rw-r-- 1 yun yun 1205 Oct 26 16:02 test_loop_hash.yml
 7 [yun@ansi-manager object04]$ cat file/config_test.conf.j2 
 8 111
 9 [yun@ansi-manager object04]$ cat file/yml_test_j2.yml 
10 222
11 [yun@ansi-manager object04]$ cat test_loop_hash.yml 
12 ---
13 # 使用循环字典创建多个用户,创建多个文件,拷贝多个文件
14 - hosts: proxyservers
15 
16   tasks:
17     - name: "Create multiple user"
18       user:
19         name: "{{ item.user }}"
20         groups: "{{ item.groups }}"
21       loop:
22         - { user: "testuser1", groups: "root" }
23         - { user: "testuser2", groups: "root,yun" }
24 
25     - name: "Create multiple file or dir"
26       file:
27         path: "{{ item.path }}"
28         owner: "{{ item.owner }}"
29         group: "{{ item.group }}"
30         mode: "{{ item.mode }}"
31         state: "{{ item.state }}"
32       loop:
33         - { path: "/tmp/with_items_testdir", owner: "yun", group: "root", mode: "755", state: "directory" }
34         - { path: "/tmp/with_items_testfile", owner: "bin", group: "bin", mode: "644", state: "touch" }
35 
36     - name: "copy multiple file"
37       copy:
38         src: "{{ item.src }}"
39         dest: "{{ item.dest }}"
40         owner: "{{ item.owner }}"
41         group: "{{ item.group }}"
42       loop:
43         - { src: "./file/config_test.conf.j2", dest: "/tmp/with_items_testdir/", owner: "yun", group: "root" }
44         - { src: "./file/yml_test_j2.yml", dest: "/tmp/yml_test.yml", owner: "yun", group: "yun" }
45 
46 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_loop_hash.yml  # 语法检测
47 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_loop_hash.yml  # 预执行,测试执行
48 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_loop_hash.yml  # 执行

使用 with_items 方式

其中 playbook 文件中仅把 loop 变为了 with_items。

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 16
 5 drwxrwxr-x 2 yun yun   56 Oct 26 16:03 file
 6 -rw-rw-r-- 1 yun yun 1205 Oct 26 16:02 test_with_items_hash.yml
 7 [yun@ansi-manager object04]$ cat file/config_test.conf.j2 
 8 111
 9 [yun@ansi-manager object04]$ cat file/yml_test_j2.yml 
10 222
11 [yun@ansi-manager object04]$ cat test_with_items_hash.yml 
12 ---
13 # 使用循环字典创建多个用户,创建多个文件,拷贝多个文件
14 - hosts: proxyservers
15 
16   tasks:
17     - name: "Create multiple user"
18       user:
19         name: "{{ item.user }}"
20         groups: "{{ item.groups }}"
21       with_items:
22         - { user: "testuser1", groups: "root" }
23         - { user: "testuser2", groups: "root,yun" }
24 
25     - name: "Create multiple file or dir"
26       file:
27         path: "{{ item.path }}"
28         owner: "{{ item.owner }}"
29         group: "{{ item.group }}"
30         mode: "{{ item.mode }}"
31         state: "{{ item.state }}"
32       with_items:
33         - { path: "/tmp/with_items_testdir", owner: "yun", group: "root", mode: "755", state: "directory" }
34         - { path: "/tmp/with_items_testfile", owner: "bin", group: "bin", mode: "644", state: "touch" }
35 
36     - name: "copy multiple file"
37       copy:
38         src: "{{ item.src }}"
39         dest: "{{ item.dest }}"
40         owner: "{{ item.owner }}"
41         group: "{{ item.group }}"
42       with_items:
43         - { src: "./file/config_test.conf.j2", dest: "/tmp/with_items_testdir/", owner: "yun", group: "root" }
44         - { src: "./file/yml_test_j2.yml", dest: "/tmp/yml_test.yml", owner: "yun", group: "yun" }
45 
46 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_with_items_hash.yml  # 语法检测
47 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_with_items_hash.yml  # 预执行,测试执行
48 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_with_items_hash.yml  # 执行

遍历字典

示例:

使用 loop 方式【推荐】

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 28
 5 -rw-rw-r-- 1 yun yun  452 Oct 26 16:46 test_loop_dict.yml
 6 [yun@ansi-manager object04]$ cat test_loop_dict.yml 
 7 ---
 8 # 打印信息
 9 - hosts: manageservers
10   vars:
11     users:
12       alice:
13         name: Alice Appleworth
14         telephone: 123-456-7890
15       bob:
16         name: Bob Bananarama
17         telephone: 987-654-3210
18 
19   tasks:
20     - name: "print user info"
21       debug:
22         msg: "User {{ item.key }}, userfullname: {{ item.value.name }} ({{ item.value.telephone }})"
23       # 将字典转换为适合循环的项表  第一种方式推荐
24       loop: "{{ users|dict2items }}"
25       #loop: "{{ lookup(\'dict\', users) }}"
26 
27 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_loop_dict.yml  # 语法检测
28 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_loop_dict.yml  # 预执行,测试执行
29 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_loop_dict.yml  # 执行

使用 with_items 方式

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 28
 5 -rw-rw-r-- 1 yun yun  458 Oct 26 16:47 test_with_items_dict.yml
 6 [yun@ansi-manager object04]$ cat test_with_items_dict.yml 
 7 ---
 8 # 打印信息
 9 - hosts: manageservers
10   vars:
11     users:
12       alice:
13         name: Alice Appleworth
14         telephone: 123-456-7890
15       bob:
16         name: Bob Bananarama
17         telephone: 987-654-3210
18 
19   tasks:
20     - name: "print user info"
21       debug:
22         msg: "User {{ item.key }}, userfullname: {{ item.value.name }} ({{ item.value.telephone }})"
23       # with_dict 会直接解析字典
24       with_dict: "{{ users }}"
25 
26 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_with_items_dict.yml  # 语法检测
27 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_with_items_dict.yml  # 预执行,测试执行
28 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_with_items_dict.yml  # 执行

变量循环-vars

针对yum 安装多个包很有用,其他则会报出警告。

 1 [yun@ansi-manager object04]$ pwd
 2 /app/ansible_info/object04
 3 [yun@ansi-manager object04]$ ll
 4 total 36
 5 -rw-rw-r-- 1 yun yun  252 Oct 26 17:46 test_cycle_vars.yml
 6 [yun@ansi-manager object04]$ cat test_cycle_vars.yml 
 7 ---
 8 # 批量包安装
 9 - hosts: proxyservers
10 
11   tasks:
12     - name: "Install multiple packages"
13       yum:
14         name: "{{ multi_package }}"
15         state: present
16       vars:
17         multi_package:
18           - tree
19           - nc
20           - tcpdump
21 
22 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key --syntax-check test_cycle_vars.yml  # 语法检测
23 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key -C test_cycle_vars.yml  # 预执行,测试执行
24 [yun@ansi-manager object04]$ ansible-playbook -b -i ../hosts_key test_cycle_vars.yml  # 执行

该方法不一定适用于其他模块

Ansible playbook 编程

触发器-handlers

当我们修改了服务的配置文件时,这时我们需要去重启服务,那么 handlers 就可以派上用场了。

注意事项:

1、无论多少个 task 通知了相同的 handlers,handlers 仅会在所有 tasks 结束后运行一次。

2、只有 task 发生改变了才会通知 handlers,没有改变则不会通知和触发 handlers。

3、不能用 handlers 替代 task 。

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 24
 5 drwxrwxr-x 2 yun yun  129 Aug 24 11:41 file
 6 -rw-rw-r-- 1 yun yun 1029 Aug 24 11:57 test_handlers.yml
 7 [yun@ansi-manager object05]$ ll file/  # 涉及配置文件
 8 total 20
 9 -rw-r--r-- 1 yun yun 11767 Aug 24 11:41 httpd.conf.j2
10 [yun@ansi-manager object05]$ vim file/httpd.conf.j2   # 配置文件修改的地方
11 …………
12 # Change this to Listen on specific IP addresses as shown below to 
13 # prevent Apache from glomming onto all bound IP addresses.
14 #
15 #Listen 12.34.56.78:80
16 ###### 端口改为变量
17 Listen {{ httpd_port }}
18 
19 …………
20 [yun@ansi-manager object05]$ cat test_handlers.yml  # yml 文件
21 ---
22 # 比如安装配置启动 httpd。当我们修改配置文件,重启 httpd 服务
23 # 要求:修改配置,重启一个或多个服务
24 - hosts: proxyservers
25   # 这里为了演示方便,因此变量直接就写在了该文件中
26   vars:
27     - httpd_port: 8081
28 
29   tasks:
30     - name: "Install httpd"
31       yum:
32         name: "{{ packages }}"
33         state: present
34       vars:
35         packages:
36           - httpd
37           - httpd-tools
38 
39     - name: "Httpd config"
40       template:
41         src: ./file/httpd.conf.j2
42         dest: /etc/httpd/conf/httpd.conf
43       # 一个通知
44       # notify: "Restart httpd server"
45       # 多个通知
46       notify:
47         - "Restart httpd server"
48         - "Restart crond server"
49 
50     - name: "Start httpd server"
51       systemd:
52         name: httpd
53         state: started
54         enabled: yes
55 
56   handlers:
57     - name: "Restart httpd server"
58       systemd:
59         name: httpd
60         state: restarted
61 
62     - name: "Restart crond server"
63       systemd:
64         name: crond
65         state: restarted
66 
67 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_handlers.yml  # 语法检测
68 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key -C test_handlers.yml  # 预执行,测试执行
69 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_handlers.yml  # 执行

任务标签-tags

默认情况下,当我们执行一个 playbook 时,会执行该 playbook 中所有的任务。如果只想执行一个 task 或者部分 task 用于调试或者需求就是执行部分 task。那么可以使用 ansible 的标签(tags)功能给单独 task 或者全部 task 打上标签。之后利用这些标签来指定要运行哪些 playbook 任务,或不运行哪些 playbook 任务。

打标签方式

对一个 task 打一个标签;

对一个 task 打多个标签;

对多个 task 打一个标签

标签如何运用

-t TAGS, –tags=TAGS:执行指定的 tag 标签任务;多个标签使用逗号分开

–skip-tags=SKIP_TAGS:跳过指定标签不执行,执行指定外的 task「标签作用于 task 上,即使该task还有其他标签,这个 task 也不会被执行」;多个标签使用逗号分开

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 8
 5 drwxrwxr-x 2 yun yun   27 Oct 26 18:07 file
 6 -rw-rw-r-- 1 yun yun 1004 Oct 26 19:21 test_tags.yml
 7 [yun@ansi-manager object05]$ cat test_tags.yml 
 8 ---
 9 # tags 标签测试
10 - hosts: proxyservers
11   # 这里为了演示方便,因此变量直接就写在了该文件中
12   vars:
13     - httpd_port: 8081
14 
15   tasks:
16     - name: "Install httpd"
17       yum:
18         name: "{{ packages }}"
19         state: present
20       vars:
21         packages:
22           - httpd
23           - httpd-tools
24       tags: 
25         - httpd_server
26         - httpd_install
27 
28     - name: "Httpd config"
29       template:
30         src: ./file/httpd.conf.j2
31         dest: /etc/httpd/conf/httpd.conf
32       notify: "Restart httpd server"
33       tags:
34         - httpd_server
35         - httpd_config
36 
37     - name: "Start httpd server"
38       systemd:
39         name: httpd
40         state: started
41         enabled: yes
42       tags: 
43         - httpd_server
44         - httpd_start
45 
46     - name: "Create dir"
47       file:
48         path: /tmp/with_items_testdir
49         state: directory
50       tags: create_dir
51 
52   handlers:
53     - name: "Restart httpd server"
54       systemd:
55         name: httpd
56         state: restarted

playbook 标签查看

 1 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_tags.yml  # 语法检测
 2 ## 查看 playbook 中的任务和标签
 3 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml --list-tasks 
 4 
 5 playbook: test_tags.yml
 6 
 7   play #1 (proxyservers): proxyservers    TAGS: []
 8     tasks:
 9       Install httpd    TAGS: [httpd_install, httpd_server]
10       Httpd config    TAGS: [httpd_config, httpd_server]
11       Start httpd server    TAGS: [httpd_server, httpd_start]
12       Create dir    TAGS: [create_dir]
13 ## 查看 playbook 中的标签
14 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml --list-tags
15 
16 playbook: test_tags.yml
17 
18   play #1 (proxyservers): proxyservers    TAGS: []
19       TASK TAGS: [create_dir, httpd_config, httpd_install, httpd_server, httpd_start]

playbook 执行

 1 ## 单个标签执行
 2 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml -t httpd_install 
 3 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml -t httpd_server
 4 ## 多个标签执行
 5 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml -t httpd_install,httpd_config,httpd_start
 6 ## 跳过哪些标签不执行「标签作用于 task 上,即使该 task 还有其他标签,这个 task 也不会被执行」
 7 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml --skip-tags httpd_server
 8 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml --skip-tags httpd_install,create_dir
 9 ## 执行整个 playbook 
10 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_tags.yml

文件引用/复用-include与import

在实际应用中,是不可能将所有 task 写在一个 playbook 中的,需要进行拆分,方便后期重复使用。这样后面写其他 playbook 的时候,如果有重复的,那么直接引用之前写的即可。

Includes 与 Imports

1、include 和 import 虽然功能相近,但是 ansible 执行引擎对他们的处理却截然不同。

2、所有 import* 语句都会在解析 playbook 时进行预处理。「提前准备好工具」

3、所有 include* 语句都是在执行 playbook 时遇到再处理。「需要什么工具,再拿什么工具」

PS:include 模块:这个模块还将支持一段时间,但在不久的将来可能会弃用「最好不要使用这个模块」。

示例

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 32
 5 drwxrwxr-x 2 yun yun  103 Aug 24 19:51 file_yml
 6 -rw-rw-r-- 1 yun yun  518 Aug 24 19:56 test_include.yml
 7 [yun@ansi-manager object05]$ ll file_yml/
 8 total 16
 9 -rw-rw-r-- 1 yun yun 136 Aug 24 19:51 httpd_config.yml
10 -rw-rw-r-- 1 yun yun 133 Aug 24 19:41 httpd_install.yml
11 -rw-rw-r-- 1 yun yun  80 Aug 24 19:42 httpd_restart.yml
12 -rw-rw-r-- 1 yun yun  93 Aug 24 19:41 httpd_start.yml
13 ## 每个小 yml 文件的具体内容
14 [yun@ansi-manager object05]$ cat file_yml/httpd_install.yml 
15 - name: "Install httpd"
16   yum:
17     name: "{{ packages }}"
18     state: present
19   vars:
20     packages:
21       - httpd
22       - httpd-tools
23 
24 [yun@ansi-manager object05]$ cat file_yml/httpd_config.yml 
25 - name: "Httpd config"
26   template:
27     src: ./file/httpd.conf.j2
28     dest: /etc/httpd/conf/httpd.conf
29   notify: "Restart httpd server"
30 
31 [yun@ansi-manager object05]$ cat file_yml/httpd_start.yml 
32 - name: "Start httpd server"
33   systemd:
34     name: httpd
35     state: started
36     enabled: yes
37 
38 [yun@ansi-manager object05]$ cat file_yml/httpd_restart.yml 
39 - name: "Restart httpd server"
40   systemd:
41     name: httpd
42     state: restarted
43 
44 ###### 主调用 yml 文件内容 ######
45 [yun@ansi-manager object05]$ cat test_include.yml 
46 ---
47 # 调用其他 yml 文件
48 - hosts: proxyservers
49   # 这里为了演示方便,因此变量直接就写在了该文件中
50   vars:
51     - httpd_port: 8083
52 
53   tasks:
54     - include_tasks: ./file_yml/httpd_install.yml
55     - include_tasks: ./file_yml/httpd_config.yml
56     - include_tasks: ./file_yml/httpd_start.yml
57 
58   handlers:
59     # 使用 import 进行预处理,这样防止 notify 时,在 handlers 找不到对应的信息
60     - import_tasks: ./file_yml/httpd_restart.yml
61 
62 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_include.yml  # 语法检测
63 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key -C test_include.yml  # 预执行,测试执行
64 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_include.yml  # 执行

忽略错误-ignore_errors

在 playbook 执行过程中,默认情况下如果有错误发生,那么后面的 task 就不执行,并且退出当前的 playbook。

如果我们对某些 task 执行结果不关心,不管执行是否成功,后面的 task 也要继续执行。那就需要通过 ignore_errors 来忽略当前 task 的错误结果,让后面的 task 继续往下执行。

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 36
 5 -rw-rw-r-- 1 yun yun  479 Aug 26 09:24 test_ignore_errors.yml
 6 [yun@ansi-manager object05]$ cat test_ignore_errors.yml 
 7 ---
 8 # ignore_errors 测试
 9 - hosts: proxyservers
10 
11   tasks:
12     - name: "Install httpd"
13       yum:
14         name: "{{ packages }}"
15         state: present
16       vars:
17         packages:
18           - httpd
19           - httpd-tools
20 
21     - name: "Shell false"
22       shell: /bin/false
23       # 是否忽略该 task 的错误 「打开或关闭注释,对比」
24       ignore_errors: True
25 
26     - name: "Create dir"
27       file:
28         path: /tmp/with_items_testdir
29         state: directory
30 
31 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_ignore_errors.yml  # 语法检测
32 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key -C test_ignore_errors.yml  # 预执行,测试执行
33 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_ignore_errors.yml  # 执行

默认情况

Ansible playbook 编程

使用了 ignore_errors 的情况

Ansible playbook 编程

自定义错误判定条件-failed_when

命令不依赖返回状态码来判定是否执行失败,而是要查看命令返回内容来决定,比如返回内容中包括 command not found 字符串,则判定为失败。

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 48
 5 -rw-rw-r-- 1 yun yun  369 Aug 29 16:12 test_custom_error.yml
 6 [yun@ansi-manager object05]$ cat test_custom_error.yml 
 7 ---
 8 # 自定义错误条件
 9 - hosts: proxyservers
10 
11   tasks:
12     - name: "this command prints \'command not found\' if not find"
13       shell: "kkk -x"  # 测试一
14       #shell: "/bin/kkk -x"  # 测试二
15       register: shell_result
16       failed_when: "\'command not found\' in shell_result[\'stderr\']"
17 
18     - name: "print shell_result info"
19       debug:
20         msg: "{{ shell_result[\'stderr\'] }}"
21 
22 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_custom_error.yml  # 语法检测
23 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key -C test_custom_error.yml  # 预执行,测试执行
24 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_custom_error.yml  # 执行

强制调用触发器-force_handlers

通常情况下,当 task 执行失败后,playbook 会终止。任何在此之前已经被 task notify 的 handlers 都不会被执行。

此时,如果你在 playbook 中设置了 force_handlers: yes 参数,则被通知的 handlers 就会被强制执行(有些特殊场景可能会使用到)。

如示例,在一个 playbook 中,如果配置文件的 task 已经被执行成功,并且 notify 了 handlers,之后必须重启服务。那么我们会强制要求:即使后续的 task 执行失败,之前被通知的 handlers 也必须执行。

如果不强制执行就变成了,第一次执行时:配置文件修改成功,但由于之后有 task 执行失败,导致 playbook 终止,后续 handlers 没有被调用,对应服务没有重启;第二次执行时:配置文件没发生改变「因此第一次已经更新了配置文件」,因此不会通知 handlers。最终结果就是配置改变了,但是就是没有重启服务。显然不符合我们的初衷。

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 40
 5 drwxrwxr-x 2 yun yun  129 Aug 24 14:28 file
 6 -rw-rw-r-- 1 yun yun  909 Aug 29 12:23 test_error_deal.yml
 7 [yun@ansi-manager object05]$ cat test_error_deal.yml 
 8 ---
 9 # 即使 task 执行错误,之前已 notify 的 handlers 必须被执行
10 - hosts: proxyservers
11   # 这里为了演示方便,因此变量直接就写在了该文件中
12   vars:
13     - httpd_port: 8087
14   # 即使 task 执行错误,之前已 notify 的 handlers 必须被执行
15   force_handlers: yes
16 
17   tasks:
18     - name: "Install httpd"
19       yum:
20         name: "{{ packages }}"
21         state: present
22       vars:
23         packages:
24           - httpd
25           - httpd-tools
26 
27     - name: "Httpd config"
28       template:
29         src: ./file/httpd.conf.j2
30         dest: /etc/httpd/conf/httpd.conf
31       notify: "Restart httpd server"
32 
33     - name: "Start httpd server"
34       systemd:
35         name: httpd
36         state: started
37         enabled: yes
38 
39     # /bin/false  返回状态码为1,不为0
40     - name: "Shell task"
41       shell: /bin/false
42 
43     - name: "Create dir"
44       file:
45         path: /tmp/with_items_testdir
46         state: directory
47 
48   handlers:
49     - name: "Restart httpd server"
50       systemd:
51         name: httpd
52         state: restarted
53 
54 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_error_deal.yml  # 语法检测
55 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key -C test_error_deal.yml  # 预执行,测试执行
56 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_error_deal.yml  # 执行

抑制changed状态-changed_when

ansible 会自动判断模块执行状态,command、shell 及其它模块如果修改了远程主机状态则被判定为 changed 状态,不过也可以自己决定达到 changed 状态的条件。

当我们在 playbook 中使用 shell 或者 command 模块时,每次 task 执行状态都是 changed。原因是因为每次我们都去执行获取当前数据,而不是一个固化的状态。

但在实际应用中,我们可能不需要 shell 或者 command 模块执行后的 changed 状态,这时我们就需要通过 changed_when: false 来抑制这个改变。

当然上述的 changed_when: false 可以在任何模块中使用,不局限于 shell 和 command 模块,只是我们常用于这两个模块而已。

 1 [yun@ansi-manager object05]$ pwd
 2 /app/ansible_info/object05
 3 [yun@ansi-manager object05]$ ll
 4 total 44
 5 -rw-rw-r-- 1 yun yun  299 Aug 29 14:47 test_changed_when.yml
 6 [yun@ansi-manager object05]$ cat test_changed_when.yml 
 7 ---
 8 # 使用 changed_when: false 抑制 changed 状态
 9 - hosts: proxyservers
10 
11   tasks:
12     - name: "Shell task"
13       shell: netstat -lntp | grep \'httpd\'
14       register: check_httpd
15       # changed_when: false  # 任何时候,都不为 changed 状态
16       #### check_httpd[\'stdout\'] 不包含 httpd 为 true,否则 false
17       changed_when: "\'httpd\' not in check_httpd[\'stdout\']" # 结果为 false 
18 
19     - name: "Debug output"
20       debug:
21         msg: "{{ check_httpd.stdout }}"
22 
23 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key --syntax-check test_changed_when.yml  # 语法检测
24 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key -C test_changed_when.yml  # 预执行,测试执行
25 [yun@ansi-manager object05]$ ansible-playbook -b -i ../hosts_key test_changed_when.yml  # 执行

未经允许不得转载:艺宵博客 » Ansible playbook 编程

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