N46-第十二周作业

1、通过ansible roles编排实现httpd角色的部署

答：

###安装ansible###
# wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-8.repo
# yum install -y https://mirrors.aliyun.com/epel/epel-release-latest-8.noarch.rpm
# dnf install -y ansible

###添加被管理ip###
# vim /etc/ansible/hosts
[appsvrs]
10.0.0.206
10.0.0.207

###进行免密码登录###
# vim ssh_key.sh

#!/bin/bash
iplist="
10.0.0.206
10.0.0.207
"
rpm -q sshpass &> /dev/null || yum install -y sshpass
[ -f /root/.ssh/id_rsa ] || ssh-keygen -f /root/.ssh/id_rsa -P ''
export SSHPASS=123456
for ip in $iplist; do
sshpass -e ssh-copy-id -o StrictHostKeyChecking=no $ip
done

# chmod +x ssh_key.sh
# ./ssh_key.sh

###创建角色目录###
# mkdir -pv /data/ansible/roles/httpd/{handlers,tasks,files}
# tree .
.
├── files
├── handlers
└── tasks

###进入角色目录###
cd /data/ansible/roles/httpd/

###创建组的yml文件###
# vim tasks/group.yml
- name: create apache group
group: name=apache gid=80 system=yes

###创建用户的yml文件###
# vim tasks/user.yml
- name: create apache user
user: name=apache uid=80 group=apache system=yes shell=/sbin/nologin home=/var/www/

###创建安装的yml文件###
# vim tasks/install.yml
- name: install httpd package
yum: name=httpd state=installed

###配制conf文件###
# vim files/conf.sh

#!/bin/bash
mkdir -p /data/html
sed -i s#'DocumentRoot "/var/www/html"'#'DocumentRoot "/data/html"'#g /etc/httpd/conf/httpd.conf
sed -i s#'<Directory "/var/www/html">'#'<Directory "/data/html">'#g /etc/httpd/conf/httpd.conf

# chmod +x ./files/conf.sh

# vim tasks/config.yml
- name: config file script
script: conf.sh
notify: restart

###创建首页文件###
# vim files/index.sh

#!/bin/bash
echo "<h1>httpd website based ansilbe.</h1>" /data/html/index.html

# chmod +x ./files/index.sh

# vim tasks/index.yml
- name: index.html script
script: index.sh

###启动服务###
# vim tasks/service.yml
- name: start service
service: name=httpd state=started enabled=yes

###创建任务的main.yml文件###
# vim tasks/main.yml
- include: group.yml
- include: user.yml
- include: install.yml
- include: config.yml
- include: index.yml
- include: service.yml

###建立handlers###
# vim handlers/main.yml
- name: restart
service: name=httpd state=restarted

###建立执行的角色yml文件###
# cd ..
# vim role_httpd.yml
---
- hosts: app
remote_user: root
roles:
- role: httpd

# tree .
.
├── httpd
│   ├── files
│   │   ├── conf.sh
│   │   └── index.sh
│   ├── handlers
│   │   └── main.yml
│   └── tasks
│   ├── config.yml
│   ├── group.yml
│   ├── index.yml
│   ├── install.yml
│   ├── main.yml
│   ├── service.yml
│   └── user.yml
└── httpd_roles.yml

###测试playbook执行###
# ansible-playbook -C httpd_roles.yml

PLAY [app] **********************************************************************************************************************************************************************************

TASK [Gathering Facts] **********************************************************************************************************************************************************************
ok: [10.0.0.206]
ok: [10.0.0.207]

TASK [httpd : create apache group] **********************************************************************************************************************************************************
changed: [10.0.0.206]
changed: [10.0.0.207]

TASK [httpd : create apache user] ***********************************************************************************************************************************************************
changed: [10.0.0.206]
changed: [10.0.0.207]

TASK [install httpd package] ****************************************************************************************************************************************************************
changed: [10.0.0.206]
changed: [10.0.0.207]

TASK [httpd : start service] ****************************************************************************************************************************************************************
changed: [10.0.0.206]
changed: [10.0.0.207]

PLAY RECAP **********************************************************************************************************************************************************************************
10.0.0.206 : ok=5 changed=4 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
10.0.0.207 : ok=5 changed=4 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0

###安装httpd###
# ansible-playbook httpd_roles.yml

PLAY [app] **********************************************************************************************************************************************************************************

# ansible app -a 'curl http://localhost'
[WARNING]: Consider using the get_url or uri module rather than running 'curl'. If you need to use command because get_url or uri is insufficient you can add 'warn: false' to this command
task or set 'command_warnings=False' in ansible.cfg to get rid of this message.
10.0.0.206 | CHANGED | rc=0 >>
<h1>httpd website based ansilbe.</h1> % Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 38 100 38 0 0 6301 0 --:--:-- --:--:-- --:--:-- 7600
10.0.0.207 | CHANGED | rc=0 >>
<h1>httpd website based ansilbe.</h1> % Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 38 100 38 0 0 38000 0 --:--:-- --:--:-- --:--:-- 38000

2、简述MySQL数据库访问的执行过程。

答：

用户通过ip或socket请求连接mysql。经过连接层判断是否合法，如果合法，分配连接相应的线程。连接层线程将用户需要执行的sql语句送到sql层处理。sql层经过语句、语义、语法、sql类型、权限等判断后，先进行缓存查询，找到则直接返回给用户数据。如果缓存没有找到，将sql送到解析器，解析后生成执行任务，优先器读取执行任务，判断并选择代价最小的执行方案。安执行计划执行，生成获取数据的方案，交由存储引擎层继续处理。存储引擎层根据上层提供的方案，获取磁盘数据返回给用户。此次查询信息会缓存至查询缓存中。

3、select语句的完整语法较复杂，但至少包括的部分是（B）
A、仅select
B、select，from
C、select，group
D、select，into

4、一张表的主键个数为（C）
A、至多3个 B、没有限制 C、至多1个 D、至多2个

posted @ 2020-08-18 09:47 索玛阅读(294) 评论(0) 收藏举报

刷新页面返回顶部

索玛

N46-第十二周作业

公告