Linux System Engineer Technology (Engineer)-------the next day

Two virtual machines, both fire and hostname modified

The firewall modifies the original----------public state---------to-------trusted state

Virtual Machine Server0:

# Firewall-cmd--set-default-zone=trusted?

# echo server0.example.com?>?/etc/hostname

# Cat/etc/hostname

Virtual Machine desktop0:

# Firewall-cmd--set-default-zone=trusted?

# echo desktop0.example.com?>?/etc/hostname

# Cat/etc/hostname

? Basic features of the e-mail server

– Provide users with an e-mail storage space (username @ mail domain name)

– Process user-sent messages-delivered to the receiving server

– Process messages received by users--post to mailbox

? ? ? User e-mail protocol:? SMTP? port 25

? ? ? User receive mail agreement:? POP3? port 110?? IMAP port 143????

? ?

######################################################

Virtual Machine Server0

Building a Basic mail server

1. Installing the Postfix service-side program

[Email protected] ~]# rpm-q postfix

Postfix-2.10.1-6.el7.x86_64

2. Configure the Postfix service, modify the configuration file

[Email protected] ~]# VIM/ETC/POSTFIX/MAIN.CF

? 76 lines? Myhostname = server0.example.com?? #指定主机名

? 83 lines? MyDomain = example.com??????? #指定域名

? 99 lines? Myorigin = server0.example.com?? #默认补全的邮件后缀

? 116 line inet_interfaces = All?????? #允许所有客户端

? 164 rows Mydestination = server0.example.com

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? #判断邮件后缀为本域邮件

????: Vim command mode??? u Undo

3. Restart Postfix service, set to boot from

# systemctl restart Postfix??????????????????

# Systemctl enable Postfix?

4. Test Mail Sending and receiving

[Email protected] ~]# Useradd YG

[Email protected] ~]# echo 123 | passwd--stdin YG

[Email protected] ~]# Useradd XLN

[Email protected] ~]# echo 123 | passwd--stdin XLN

? Mail sending operation

–mail-s ' mail header '? -R sender?? recipient

? Mail receive operation

–mail [-u user Name]

[Email protected] ~]# mail-s ' test01 '-R YG? Xln

? There is only one in a row. "."?? when the representative ends

?

[Email Protected]rver0 ~]# mail-u XLN

? Enter message number 1 view message content

? Quit quitting

################################################# ?

Nullclient Mail Service

Empty client

? Nullclient, empty Client

– No email account is available, so no mail is required

– but you can send a message to the user on behalf of

I. Configuring DESKTOP0 as a mail server

1. Configure the Postfix service, modify the configuration file

[Email protected] ~]# VIM/ETC/POSTFIX/MAIN.CF

? 99 line?? myorigin = desktop0.example.com??

? 116 line? inet_interfaces = All??????

? 164 line? mydestination = desktop0.example.com

[Email protected] ~]# systemctl restart Postfix

[Email protected] ~]# Systemctl enable Postfix

Second, configure SERVER0 to be empty client mail server

[Email protected] ~]# vim/etc/postfix/main.cf?

? 99 lines?? Myorigin = desktop0.example.com

? 116 lines? inet_interfaces = localhost

? 164 lines? Mydestination =?

? 317 lines? Relayhost = [172.25.0.10]? #指定交给邮件服务器IP地址

? ?

[Email protected] ~]# systemctl restart Postfix

Third, testing

On the virtual machine Server0

# echo? ABC? |? Mail-s test1-r YG? Student

On the virtual machine desktop0

# Mail-u Student

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? database service Basics

? A common relational database management system

– Microsoft's SQL Server

–IBM's DB2

– Oracle, MySQL for Oracle

– Community Open Source version MariaDB

? MariaDB related packages in RHEL7

–mariadb-server: Provision of server-side related system programs

???????? Port number: 3306

I. Deployment of the MARIADB database

1. Installing the Mariadb-server database software

[Email protected] ~]# yum-y install Mariadb-server

2. Start the MARIADB service

[Email protected] ~]# systemctl restart MARIADB

[Email protected] ~]# Systemctl enable MARIADB

##################################################

[[email protected] ~]# MySQL?

MariaDB [(None)]> show databases;????? #查看数据库

MariaDB [(None)]> CREATE Database nsd1709;? #创建数据库

MariaDB [(None)]> show databases;?????

MariaDB [(None)]> drop database nsd1709;?? #删除数据库

MariaDB [(None)]> show databases;

MariaDB [(None)]> CREATE Database nsd;??

MariaDB [(None)]> show databases;

MariaDB [(none)]> quit???????????????? #退出数据库

###################################################

? ? ? The database administrator is root, but it does not matter to the system user root

? Change password for database account

–mysqladmin [-u user name] [-p[old password]] password ' new password '

[Email protected] ~]# mysqladmin-u? root? Password? ' 123 '

[[email protected] ~]# MySQL

ERROR 1045 (28000): Access denied for user ' root ' @ ' localhost ' (using Password:no)

[email protected] ~]# mysql?-u root?-P

Enter Password:?

[Email protected] ~]# mysql-u root-p123??? #免交互登陆

? Prohibit listening, only serve native-----------------means only to the native service, other users cannot access the database

[Email protected] ~]# vim/etc/my.cnf? #数据库主配置文件

[Mysqld]

Skip-networking???? #跳过网络监听

......

[Email protected] ~]# systemctl restart MARIADB

? MariaDB [(none)]> Interactive Instruction

---------------List database: show databases;

---------------/Select database: Use database name;

--------------lists which tables are in the library: show tables;

--------------Creating database: Create database name;

-----------Delete database: drop database name;

Http://172.25.254.254/pub/materials/users.sql

? Import/Restore to Database

–mysql [-u user name] [-p[password]] Database name?< backup file. sql

# wget Http://172.25.254.254/pub/materials/users.sql

# mysql-u root-p123 NSD < Users.sql

# mysql-u Root-p123

MariaDB [nsd]> use NSD;????? #进入nsd库

MariaDB [nsd]> show tables;??? #查看都有那些表格

######################################################

? query operations

# mysql-u Root-p123

MariaDB [nsd]> use NSD;

MariaDB [nsd]> SELECT * from base;

MariaDB [nsd]> SELECT * from location;

MariaDB [nsd]> Select Id,name from base;

MariaDB [nsd]> SELECT * from base where name= ' Tom ';

MariaDB [nsd]> SELECT * from location where city= ' Beijing ';

#######################################################

? Database authorization

MariaDB [(none)]> Interactive Instruction

–grant permissions list? The database name. Table name? To? user name @localhost

? Identified by ' Password '

?? When the Lisi user logs in from localhost, enter password 123, and the Library NSD all table query permissions

# mysql-u Root-p123

MariaDB [(None)]> Grant Select on nsd.* to [e-mail protected] identified by ' 123 ';

View the user table information in the MARIADB database

MariaDB [mysql]> Select User,password from Mysql.user;

#####################################################

Case 5: Working with database queries

2. Use the database NSD on the system Server0 and use the phase

The SQL query that is expected to answer the following questions:

1) password is the name of the person who solicitous?

> select * from nsd.base where password= ' solicitous ';

> select * from nsd.base where password= ' solicitous ' and? id= ' 3 ';

> select * from nsd.base where name= ' Barbara ' or? id= ' 3 ';

2) How many people's names are Barbara while residing in Sunnyvale?

> Use NSD;

> select * from Base,location

where Base.name= ' Barbara ' and location.city= ' Sunnyvale '? and? Base.id=location.id;

> select COUNT (*) from base,location??

where Base.name= ' Barbara ' and location.city= ' Sunnyvale ' and? Base.id=location.id;

> Insert Base VALUES (6, ' Barbara ', 123456);? #插入表记录

> Insert Location VALUES (6, ' Sunnyvale ');? #插入表记录

> select * from base;

> select * from location;

1. Disable null password root user access to MARIADB database

> Use MySQL;

> select User,host,password from user where password= ' and user= ' root ';

> Delete from user where password= ' and user= ' root ';------Delete with root username and empty password

> select User,host,password from User;

> desc. user;? #查看表结构

Linux System Engineer Technology (Engineer)-------the next day