Ansible之流程控制—4
2019-10-13 本文已影响0人
静如止水yw
判断语句
循环语句
触发器 handlers
tag标签
文件复用
忽略错误
异常处理
一、判断语句
- centos和ubuntu系统都需要安装httpd, 判断系统.
- 安装软件仓库,只有web组的安装webtatic其他的主机全部跳过.
- TASK任务, TASK1任务执行成功,才会执行TASK2
#案例一 根据不同的系统,安装不同的服务
[root@manager project1]# cat f15.yml
- hosts: webservers
tasks:
- name: CentOS Installed Httpd Server
yum:
name: httpd
state: present
when: ( ansible_distribution == "CentOS" )
- name: Ubuntu Installed Httpd Server
yum:
name: httpd2
state: present
when: ( ansible_distribution == "Ubuntu" )
# 案例二、所有为问问主机的名称的添加nginx仓库，其余的都跳过添加
[root@manager project1]# cat f16.yml
- hosts: all
tasks:
- name: Add Nginx Yum Repository
yum_repository:
name: nginx
description: Nginx Repository
baseurl: http://nginx.org/packages/centos/7/$basearch/
when: ( ansible_hostname is match ("web*"))
# 根据命令的执行结果进行判断
① 通过register将命令执行结果保存至变量，然后通过when语句进行判断
[root@manager project1]# cat f17.yml
- hosts: webservers
tasks:
- name: Check Httpd Server
command: systemctl is-active httpd
register: Check_Httpd
ignore_errors: yes
#判断Check_Httpd.rc是否等于0,如果为0则执行任务,否则不执行
- name: Restart Httpd Server
systemd:
name: httpd
state: restarted
when: ( Check_Httpd.rc == 0 )
二、Playbook循环语句
循环语句的优点就是减少了重复性的工作。
# 一次启动多个服务
[root@manager~/project1]# cat f18.yml
- hosts: webservers
tasks:
- name: Systemd Nginx Status
systemd:
name: "{{ item }}" #调用的变量也不变，也是固定。
state: started
# 固定的语法格式
with_items:
- nginx
- php-fpm
# 一次拷贝多个文件
[root@manager~/project1]# cat f19.yml
- hosts: webservers
tasks:
- name: Configure nginx.conf
copy:
src: './file/{{ item.src }}'
dest: './file{{ item.dest }}'
mode: '{{ item.mode }}'
with_items:
- { src: nginx.conf.j2, dest: /etc/nginx/nginx.conf, mode: '0644' }
- { src: /kod.oldxu.com.conf.j2, dest: /etc/nginx/conf.d/kod.oldxu.com.conf, mode: '0600' }
# 一次创建多个用户(比如创建三个用户)
[root@manager~/project1]# cat f20.yml
- hosts: webservers
tasks:
- name: Create User
user:
name: '{{ item.name }}'
groups: '{{ item.groups}}'
uid: "{{ item.uid }}"
create_home: no
shell: /sbin/nologin
with_items:
- {name: tt1, groups: bin, uid: 6666}
- {name: tt2, groups: root, uid: 8888}
- {name: tt3, groups: adm, uid: 9999}
总结
1.标准循环
item
with_items:
- test
2.字典循环:
itme.name
with_items:
- { name: test }
3.变量循环
[root@manager project1]# cat f21.yml
- hosts: webservers
tasks:
- name: ensure a list of packages installed
yum: name={{ packages }} state=present
vars:
packages:
- httpd
- httpd-tools
三、触发器handlers
Handlers是一个触发器，也是一个tasks，只不过是一个特殊的tasks，他是需要被tasks触发才会运行。
如果配置文件发生变更，则会触发重启，否则，不会触发重启。
- playbook安装nginx示例
[root@manager project1]# cat f22.yml
- hosts: webservers
tasks:
- name: Installed Nginx and PHP Packages
yum:
name: nginx
state: present
- name: Configure nginx.conf
template:
src: ./file/nginx.conf.j2
dest: /etc/nginx/nginx.conf
#监控-->changed状态-->通知-->handlers--->name-->Restart Nginx Server
notify: Restart Nginx Server
#notify:
# - Restart Nginx Server
# - Restart php Server
- name: Systemd Nginx Server
systemd:
name: nginx
state: started
enabled: yes
#当nginx或php配置文件发生变更才会触发此操作
handlers:
- name: Restart Nginx Server
systemd:
name: nginx
state: restarted
Handlers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，没有改变则不会触发handlers.
3.不能使用handlers替代tasks、因为handlers是一个特殊的tasks。
**案例一、安装redis
要求：bind本地IP地址（{{ansible_eth1.ipv4.address}}） facts都要使用
[root@manager~/project1]# cat file/redis.conf.j2
bind 127.0.0.1 {{ansible_eth1.ipv4.address}}i
[root@manager~/project1]# cat redis.yml
- hosts: redisservers
tasks:
- name: Installed Redis Server
yum:
name: redis
state: present
- name: Configure Redis Server
template:
src: ./file/redis.conf.j2
dest: /etc/redis.conf
backup: yes
notify: Restart Redis Server
- name: Sytemd Redis Server
systemd:
name: redis
state: started
enabledi: yes
- name: Check Redis Status
shell: netstAT -lntp | grep redis
register: Check_Redis
- name: Debug Check_Redis Vsariables
debug:
msg: "Redis Status:{{ Check_Redis_Status }}"
handlers:
- name: Restart Redis Server
systemd:
name: redis
state: restarted
enabled: yes
案例二 安装rsync
要求
使用循环 rsync.conf的权限为0644 rsync.passwd的权限为0600
[root@manager~/project1]# cat file/rsyncd.conf.j2
uid = rsync
gid = rsync
port = 873
fake super = yes
use chroot = no
max connections = 200
timeout = 600
ignore errors
read only = false
list = false
auth users = rsync_backup
secrets file = /etc/rsync.passwd
log file = /var/log/rsyncd.log
[backup]
comment = welcome to oldboyedu backup!
path = /backup
[data]
path = /data
[root@manager~/project1]# cat file/rsync.passwd.j2
rsync_backup:123456
[root@manager~/project1]# cat rsync.yml
- hosts: backupservers
tasks:
#1.安装Rsync
- name: Installed Rsyncd Server
yum:
name: rsync
state: present
disablerepo: webtatic-php
#2.配置rsync
- name: Configure Rsyncd Server
template:
src: "{{ item.src }}"
dest: "{{ item.dest }}"
mode: "{{ item.mode }}"
with_items:
- { src: './file/rsyncd.conf.j2', dest: '/etc/rsyncd.conf', mode: '0644' }
- { src: './file/rsync.passwd.j2', dest: '/etc/rsync.passwd', mode: '0600' }
notify: Restart Rsyncd Server
#3.根据rsync配置初始化 进程用户|虚拟连接用户文件|备份模块仓库
- name: Create Process User
user:
name: rsync
create_home: no
shell: /sbin/nologin
- name: Create Rsyncd Repo Directory
file:
path: "{{ item }}"
state: directory
owner: rsync
group: rsync
mode: 0755
with_items:
- /backup
- /data
#4.启动rsync
- name: Systemd Rsyncd Server
systemd:
name: rsyncd
state: started
enabled: yes
handlers:
- name: Restart Rsyncd Server
systemd:
name: rsyncd
state: restarted
四、tag标签
默认情况下，Ansible在执行一个playbook是，会执行playbook中定义的所有任务。Ansible的标签功能都可以给单独任务甚至整个playbook打上标签，然后利用这些标签来制定运行playbook中的个别任务，或不执行指定的任务。
打标签的方式
一个task可以打一个标签，多个任务也可以打一个标签或一个任务打多个标签
如何使用标签
-t 执行指定的tag标签任务
--skip-tags 执行--skip-tags之外的标签任务
[root@manager tasks]# cat task_nfs.yml
- hosts: webservers
tasks:
#对一个任务打多个标签
- name: Install Nfs Server
yum:
name: nfs-utils
state: present
tags:
- install_nfs
- install_nfs-server
#对一个任务打一个标签
- name: Service Nfs Server
service:
name: nfs-server
state: started
enabled: yes
tags: start_nfs-server
ansible-playbook -i ../hosts task_nfs.yml -t start_nfs-server123
ansible-playbook -i ../hosts task_nfs.yml --skip-tags install_nfs-server
四、文件复用（Include包含）
[root@manager~/project1]# cat restart_nginx.yml
- name: Restart Nginx Server
systemd:
name: nginx
state: restarted
[root@manager~/project1]# cat a_project.yml
- hosts: webservers
tasks:
- name: A Project command
command: echo "A"
- name: Restart nginx
include: ./restart_nginx.yml
[root@manager~/project1]# cat b_project.yml
- hosts: webservers
tasks:
- name: B Project command
command: echo "B"
- name: Restart nginx
include: restart_nginx.yml
五、忽略错误
默认Playbook会检测tasks执行的返回状态，如果玉带错误则会立即终止playbook的后续的task执行。然而当执行出现错误，加入ignore_errors:yes之后，则会忽略错误，且后续的任务仍将执行。
[root@manager~/project1/task]# cat task_ignore.yml
- hosts: webservers
tasks:
#明确知道该TASK可能会报错,及时报错也希望不影响后续的TASK任务时
- name: Ignore False
command: /bin/false
ignore_errors: yes
- name: touch new file
file: path=/tmp/bgx_ignore state=touch
六、异常处理
1.每次状态都是changed,纵使没有修改过被控端
[root@manager~/project1]# cat redis.yml
- hosts: redisservers
tasks:
- name: Installed Redis Server
yum:
name: redis
state: present
- name: Configure Redis Server
template:
src: ./file/redis.conf.j2
dest: /etc/redis.conf
backup: yes
notify: Restart Redis Server
- name: Sytemd Redis Server
systemd:
name: redis
state: started
enabledi: yes
#Check_Redis_Status=$(netstat -lntp | grep redis)
- name: Check Redis Status
shell: netstAT -lntp | grep redis
register: Check_Redis
changed_when: false
#echo ${Check_Redis_Status}
- name: Debug Check_Redis Vsariables
debug:
msg: "Redis Status:{{ Check_Redis_Status.stdout_lines }}"
#接收通知--->触发重启Redis操作
handlers:
- name: Restart Redis Server
systemd:
name: redis
state: restarted
enabled: yes
2.nginx推送配置文件
第一种方式
[root@manager tasks]# cat task_nginx.yml
- hosts: webservers
tasks:
#安装nginx
- name: Installed nginx Server
yum:
name: nginx
state: present
#配置nginx
- name: Configure nginx Server
template:
src: ./file/nginx.conf.j2
dest: /etc/nginx/nginx.conf
#检查nginx (Check_Nginx_Status=$(nginx -t))
- name: Check Nginx Configure File
shell: nginx -t
register: Check_Nginx_Status
changed_when:
- Check_Nginx_Status.stdout.find('successful')
- false
#启动Nginx
- name: Systemd Nginx Server
systemd:
name: nginx
state: started
enabled: yes
第二种方式
[root@manager tasks]# cat task_nginx.yml
- hosts: webservers
tasks:
#安装nginx
- name: Installed nginx Server
yum:
name: nginx
state: present
#配置nginx
- name: Configure nginx Server
template:
src: ./file/nginx.conf.j2
dest: /etc/nginx/nginx.conf
#检查nginx (Check_Nginx_Status=$(nginx -t))
- name: Check Nginx Configure File
shell: nginx -t
#启动Nginx
- name: Systemd Nginx Server
systemd:
name: nginx
state: started
enabled: yes
强制调用handlers
[root@manager tasks]# cat task_nginx.yml
- hosts: webservers
force_handlers: yes #无论tasks失败与否,只要通过过handlers,那me一定会执行
tasks:
#安装nginx
- name: Installed nginx Server
yum:
name: nginx
state: present
#配置nginx
- name: Configure nginx Server
template:
src: ./file/nginx.conf.j2
dest: /etc/nginx/nginx.conf
notify: Restart Nginx Server
#检查nginx (Check_Nginx_Status=$(nginx -t))
- name: Check Nginx Configure File
shell: nginx -t
#启动Nginx
- name: Systemd Nginx Server
systemd:
name: nginx
state: started
enabled: yes
handlers:
- name: Restart Nginx Server
systemd:
name: nginx
state: restarted
