Linux Apps Tutorials - Herong's Tutorial Examples - v1.02, by Herong Yang
MySQL Server Socket Connection on CentOS
This section provides a tutorial example on how to use the Socket Connection for client programs from the same host as the MySQL 8 Server on CentOS 8 systems.
MySQL server supports 2 types of connections from client programs:
Socket Connection works under the following rules:
1. By default, the Socket Connection is turned on for MySQL 8 server.
2. Socket Connection is represented with socket files on CentOS system with "mysqlx_socket" and "socket" variables for their locations:
mysql> show variables like '%socket'; +---------------+----------------------------+ | Variable_name | Value | +---------------+----------------------------+ | mysqlx_socket | /var/lib/mysql/mysqlx.sock | | socket | /var/lib/mysql/mysql.sock | +---------------+----------------------------+
3. Users must be created with "localhost" as host named to use the Socket Connection. For example, "root" and "herong" are users who can use the Socket Connection based on the mysql.user records:
mysql> select user, host from mysql.user; +------------------+-----------+ | user | host | +------------------+-----------+ | mysql.infoschema | localhost | | mysql.session | localhost | | mysql.sys | localhost | | root | localhost | | herong | localhost | +------------------+-----------+
4. Client programs must use "localhost" as the host name to use the Socket Connection. For example, the following PHP statement will connect to the MySQL server using the Socket Connection:
$conn = mysqli_connect("localhost", 'herong', 'TopSecret');
5. MySQL client tools connect to the SQL server use the Socket Connection with the default "-h localhost" option. See the example below:
herong$ mysql -u herong -p Enter password: junk<Enter> ERROR 1045 (28000): Access denied for user 'herong'@'localhost' ...
Socket Connection is more secure. But it only allows connections from the same host as the MySQL server. To allow connections from a remote host, you have to use the TCP/IP connection as shown in the next tutorial.
Table of Contents
Running Apache Web Server (httpd) on Linux Systems
Running PHP Scripts on Linux Systems
►Running MySQL Database Server on Linux Systems
Install MySQL Database Server on CentOS
Manage MySQL Server 'mysqld' on CentOS
Set MySQL Server "root" Password on CentOS
MySQL Server File Locations on CentOS
MySQL Server Data Backups on CentOS
MySQL Server Log Files on CentOS
►MySQL Server Socket Connection on CentOS
MySQL Server TCP/IP Connection on CentOS
Open Firewall for MySQL Server on CentOS
"Server sent charset unknown to the client" Error
Performance of Inserting Integers to MySQL Database
Performance Comparison of Inserting Integers vs. Strings
Running Python Scripts on Linux Systems
Conda - Environment and Package Manager