How do I install MySQL server 8.0 on CentOS 8 Linux server running on Linode and AWS cloud? How do I add and set up a new MySQL user and database account on the newly created CentOS server?

Oracle MySQL server version 8.0 is a free and open-source free database server. It is one of the most popular database system used in web apps and websites on the Internet.

Typically MySQL is part of the LAMP (Linux, Apache/Nginx, MySQL, Perl/Python/PHP) stack. Popular open-source software such as WordPress, MediaWiki, and others profoundly used by MySQL as a database storage engine. Let us see how to install MySQL server version 8.x on CentOS 8 Linux server.

How to install MySQL server on a CentOS 8

First, open the terminal app and then log in to your CentOS server using the ssh command:
$ ssh vivek@centos-8-ec2-box-ip
Now, update CentOS system to apply security updates and fixes on Linux system using the dnf command/yum command:
$ sudo yum update
## or ##
$ sudo dnf update
Sample outputs:

CentOS-8 - AppStream                            21 MB/s | 5.8 MB     00:00    
CentOS-8 - Base                                 14 MB/s | 2.2 MB     00:00    
CentOS-8 - Extras                               50 kB/s | 8.6 kB     00:00    
Dependencies resolved.
Nothing to do.
Complete!

Step 1 – Installing MySQL 8 server

Luckily our CentOS 8 box comes with MySQL 8 server package. Let us search for it:
$ sudo yum search mysql-server
$ sudo yum module list mysql
And we see:

Last metadata expiration check: 0:02:47 ago on Mon Nov 23 16:26:31 2020.
===================== Name Exactly Matched: mysql-server ======================
mysql-server.x86_64 : The MySQL server and related files

Next, find out version information, run:
$ sudo yum info mysql-server
Here is what we see:

Last metadata expiration check: 0:02:22 ago on Mon Nov 23 16:26:31 2020.
Available Packages
Name         : mysql-server
Version      : 8.0.21
Release      : 1.module_el8.2.0+493+63b41e36
Architecture : x86_64
Size         : 22 M
Source       : mysql-8.0.21-1.module_el8.2.0+493+63b41e36.src.rpm
Repository   : AppStream
Summary      : The MySQL server and related files
URL          : http://www.mysql.com
License      : GPLv2 with exceptions and LGPLv2 and BSD
Description  : MySQL is a multi-user, multi-threaded SQL database server. MySQL
             : is a client/server implementation consisting of a server daemon
             : (mysqld) and many different client programs and libraries. This
             : package contains the MySQL server and some accompanying files
             : and directories.

Install it:
$ sudo yum install mysql-server

Click to enlarge

Step 2 – Enabling MySQL 8 mysqld.service,server

The service name is mysqld.service, and we need to enable it using the following systemctl command:
$ sudo systemctl enable mysqld.service
Confirmation displayed:

reated symlink /etc/systemd/system/multi-user.target.wants/mysqld.service → /usr/lib/systemd/system/mysqld.service.

Start the service and then verify it:
$ sudo systemctl start mysqld.service
$ sudo systemctl status mysqld.service

● mysqld.service - MySQL 8.0 database server
   Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
   Active: active (running) since Mon 2020-11-23 16:50:14 UTC; 4s ago
  Process: 551 ExecStopPost=/usr/libexec/mysql-wait-stop (code=exited, status=0/SUCCESS)
  Process: 681 ExecStartPost=/usr/libexec/mysql-check-upgrade (code=exited, status=0/SUCCESS)
  Process: 601 ExecStartPre=/usr/libexec/mysql-prepare-db-dir mysqld.service (code=exited, status=0/SUCCESS)
  Process: 577 ExecStartPre=/usr/libexec/mysql-check-socket (code=exited, status=0/SUCCESS)
 Main PID: 637 (mysqld)
   Status: "Server is operational"
    Tasks: 39 (limit: 24960)
   Memory: 331.0M
   CGroup: /system.slice/mysqld.service
           └─637 /usr/libexec/mysqld --basedir=/usr

Nov 23 16:50:13 centos-aws-mysql systemd[1]: Stopped MySQL 8.0 database server.
Nov 23 16:50:13 centos-aws-mysql systemd[1]: Starting MySQL 8.0 database server...
Nov 23 16:50:14 centos-aws-mysql systemd[1]: Started MySQL 8.0 database server.

Step 3 – Securing MySQL 8 server

All you need to do is type the following command, and it will secure MySQL 8 server installation on CentOS Linux:
$ sudo mysql_secure_installation

Please set the password for root here.

New password: 

Re-enter new password: 

Estimated strength of the password: 100 
Do you wish to continue with the password provided?(Press y|Y for Yes, any other key for No) : y
By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.

Remove anonymous users? (Press y|Y for Yes, any other key for No) : y
Success.


Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.

Disallow root login remotely? (Press y|Y for Yes, any other key for No) : y
Success.

By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.


Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y
 - Dropping test database...
Success.

 - Removing privileges on test database...
Success.

Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.

Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y
Success.

All done! 

Step 4 – Starting/Stopping/Restarting MySQL 8 server

The syntax is:
$ sudo systemctl start mysql.service
$ sudo systemctl stop mysql.service
$ sudo systemctl restart mysql.service
To view the MySQL 8 service log as follows using the journalctl command:
$ sudo journalctl -u mysqld.service -xe
$ sudo tail -f /var/log/mysql/mysqld.log
MySQL 8 log file sample entries:

2020-11-23T16:55:19.101316Z 0 [System] [MY-013172] [Server] Received SHUTDOWN from user . Shutting down mysqld (Version: 8.0.21).
2020-11-23T16:55:21.728819Z 0 [Warning] [MY-010909] [Server] /usr/libexec/mysqld: Forcing close of thread 10  user: 'root'.
2020-11-23T16:55:23.083389Z 0 [System] [MY-010910] [Server] /usr/libexec/mysqld: Shutdown complete (mysqld 8.0.21)  Source distribution.
2020-11-23T16:56:19.225544Z 0 [System] [MY-010116] [Server] /usr/libexec/mysqld (mysqld 8.0.21) starting as process 524
2020-11-23T16:56:19.237500Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2020-11-23T16:56:19.562441Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2020-11-23T16:56:19.677202Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/lib/mysql/mysqlx.sock
2020-11-23T16:56:19.754024Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2020-11-23T16:56:19.754207Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.
2020-11-23T16:56:19.780843Z 0 [System] [MY-010931] [Server] /usr/libexec/mysqld: ready for connections. Version: '8.0.21'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  Source distribution.

Step 5 – Testing MySQL 8 installation

So far, so good. You learned how to install, set up, secure, and start/stop the MySQL 8 on CentOS 8 Linux cloud server. It is time to log in as a
mysql root user. The syntax is:
$ mysql -u root -p
$ mysql -u USER -h host -p
$ mysql -u USER -h host -p mysql
Let us type a few SQL commands at the mysql> prompt:
STATUS;
SHOW VARIABLES LIKE "%version%";
quit

Step 6 – Creating a new MySQL 8 database and user account with password

Let create a new database called ‘spacedb‘, type at the mysql> prompt:
CREATE DATABASE spacedb;
Next, we are going to create a new user named ‘mars‘ for our database called ‘spacedb’ as follows:
CREATE USER 'mars'@'%' IDENTIFIED BY 'User_Password_Here';
Finally, give permissions:
GRANT SELECT, INSERT, UPDATE, DELETE ON spacedb.* TO 'mars'@'%';
Of course, we can grant ALL PRIVILEGES too as follows:
GRANT ALL PRIVILEGES ON spacedb.* TO 'mars'@'%';
See MySQL 8 users and their grants/permissions as follows:
SELECT user,host FROM mysql.user;
SHOW GRANTS for mars;
quit
Test new user settings and DB as follows:
mysql -u mars -p spacedb
mysql -u mars -h localhost -p spacedb

Where,

• -u mars; : User name for login
• -h localhost : Connect to server named localhost
• -p : Prompt for password
• spacedb : Connect to database named spacedb

Step 7 – Configuring MySQL 8 server on a CentOS 8

Let us see default config file using the cat command:
# cat /etc/my.cnf.d/mysql-server.cnf
Config:

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-error=/var/log/mysql/mysqld.log
pid-file=/run/mysqld/mysqld.pid

Want to allow remote connections to your MySQL server? Edit the /etc/my.cnf.d/mysql-server.cnf and append the following line under [mysqld]:
bind_address = 0.0.0.0

WARNING: See MySQL documentation for a detailed explanation for tuning options as to each server and set up is unique. Do not set up values blindly. I provide them as a starting point for optimizing MySQL 8 installation and values depending upon available RAM, CPU cores, server load and other circumstances.

Set InnoDB settings:

default_storage_engine          = InnoDB
innodb_buffer_pool_instances    = 1
innodb_buffer_pool_size         = 512M
innodb_file_per_table           = 1
innodb_flush_log_at_trx_commit  = 0
innodb_flush_method             = O_DIRECT
innodb_log_buffer_size          = 16M
innodb_log_file_size            = 512M
innodb_stats_on_metadata        = 0
innodb_read_io_threads          = 64
innodb_write_io_threads         = 64

MyISAM settings:

# UPD
key_buffer_size                 = 32M   
low_priority_updates            = 1
concurrent_insert               = 2
# UPD
max_connections                 = 100   
back_log                        = 512
thread_cache_size               = 100
thread_stack                    = 192K
interactive_timeout             = 180
wait_timeout                    = 180

Buffer settings UPD:

join_buffer_size                = 4M    
read_buffer_size                = 3M    
read_rnd_buffer_size            = 4M    
sort_buffer_size                = 4M

Edit and config logging if needed (by default slow_query disabled):

log_queries_not_using_indexes   = 1
long_query_time                 = 5
#slow_query_log                  = 0     
#slow_query_log_file             = /var/log/mysql/mysql_slow.log

This is useful for mysqldump command to make backups:

[mysqldump]
quick
quote_names
max_allowed_packet              = 64M

Step 8 – Firewall configuration to open MySQL server TCP port 3306

Are you using MySQL 8 server remotely? Do you have Apache/Nginx/PHP/Python/Perl app on another server? Then open port for everyone:
$ sudo firewall-cmd --zone=public --add-service=mysql --permanent
Only allow access from 192.168.1.0/24 CIDR:
$ sudo firewall-cmd \
--add-rich-rule 'rule family="ipv4" \
source address="192.168.1.0/24" \
service name="mysql" accept' --permanent
The above is fine grained firewalld access rules to restrict access to MySQL 8 server to VLAN users only. See how to set up a firewall using FirewallD on CentOS 8 Linux for more info.

Conclusion

And there you have it, Oracle MySQL server version 8.x set up and running correctly on a CentOS Linux 8 server with Firewalld config. Further, you learned how to add a new database, user, and password for your project including MySQL 8 server tuning options.