Databases

WordPress translate month names


function translate_archive_month($list) {
$patterns = array(
'/January/', '/February/', '/March/', '/April/', '/May/', '/June/',
'/July/', '/August/', '/September/', '/October/', '/November/', '/December/'
);
$replacements = array(
'Janar', 'Shkurt', 'Mars', 'Prill', 'Maj', 'Qershor',
'Korrik', 'Gusht', 'Shtator', 'Tetor', 'Nentor', 'Dhjetor'
);
$list = preg_replace($patterns, $replacements, $list);
return $list;
}

How to Setup SSL in Varnish Cache

I don’t think it is necessary to explain what a Varnish Cache is and how it affects the load speed of the site. At least not in this post. If you are here, I suppose that you want to know how to setup SSL in Varnish.

In fact, the developer of Varnish finds it a bad idea to implement SSL support. But there are still several ways to tackle this issue.

Option 1

First, you need to understand whether it is possible to handle SSL with another service and leave communication with the server on which Varnish is installed at the default port.

Example: DigitalOcean offers Fully Managed SSL Certificates. In other words, you can create a Load Balancer and configure SSL.

Then, create a droplet on the internal network (without access from the outside), raise the environment (Varnish and other software), and attach it to the Load Balancer.

But before you start, I want to highlight that you should make sure that your hosting provider offers some solutions (Cloud Flare, etc).

Option 2

Let’s imagine that we have to raise the environment to implement the API (monolith) on Laravel Framework, and we have our own VPS with root access.

The process looks like this:

  • Nginx handles the 443 port, handles static assets and proxy other requests to another Varnish Cache:6081.
  • Varnish checks the cache, and if not then proxy request to the backend (Nginx: 81, why Nginx and not PHP I will write below), gets the result, caches, and gives Nginx.
  • Nginx: 81 handle requests and run PHP on 9000 port or a socket.
  • PHP launches Laravel… It’s no longer interesting to us, we’ve known it for a long time.

So the scheme in short:

Nninx: 443 -> Varnish: 6081 -> Nginx: 81 -> PHP: 9000

Why doesn’t Varnish apply directly to PHP? Because PHP-FPM does not understand Varnish requests, and you will most likely get a 503 error.

Laravel, by the way, is a good solution since they “play nice together.”

I will skip boring guides on installing LEMP and concentrate your attention on configs.

Virtualhost for Nginx: /etc/nginx/conf.d/api.myserver.com.conf

server {

    listen 443;

    server_name www.api.myserver.com api.myserver.com;
    
    access_log   /var/log/nginx/access.log;
    error_log    /var/log/nginx/error.log;

    location = /favicon.ico { access_log off; log_not_found off; }
    location = /robots.txt  { access_log off; log_not_found off; }

    location / {
        proxy_pass http://127.0.0.1:6081;
        proxy_set_header Host $http_host;
        proxy_set_header X-Forwarded-Host $http_host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto https;
        proxy_set_header HTTPS "on";
    }

   location ~ /\.ht {
       deny all;
   }

   location ~ /.well-known {
       allow all;
   }

    # I used letsencrypt service )

    ssl_certificate /etc/letsencrypt/live/myserver.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/myserver.com/privkey.pem;
    include /etc/letsencrypt/options-ssl-nginx.conf;
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
}

server {

    listen 80;

    server_name  www.api.myserver.com api.myserver.com;

    return 301 https://www.$host$request_uri;

}

server {

    listen 81;

    server_name api.myserver.com www.api.myserver.com;

    root /var/www/api/public;

    index index.php;

    access_log   /var/log/nginx/access.log;
    error_log    /var/log/nginx/error.log;

    location / {
        try_files $uri $uri/ /index.php?$args;
    }

    location ~ .php$ {
	    include snippets/fastcgi-php.conf;
        fastcgi_param HTTPS on;
        fastcgi_pass   127.0.0.1:9000; # OR unix:/var/run/php7.4-fpm.sock;
    }
}

I used this template. You just have to modify the backend port.

# /etc/varnish/default.vcl
...

backend server1 { # Define one backend
  .host = "127.0.0.1";    # IP or Hostname of backend
  .port = "81";           # Port Nginx or whatever is listening
  .max_connections = 300; # That's it

...

/etc/default/varnish

...

DAEMON_OPTS="-a :6081 \ # input
             -T localhost:6082 \ # admin
             -f /etc/varnish/default.vcl \ # proxy conf
             -S /etc/varnish/secret \ # secret conf
             -s malloc,256m" 

...

That’s all. Those simple maneuvers can significantly accelerate a project. I hope this little guide will help you save your time and reduce your suffering.

Introduction to Installing htop on CentOS 7

any sysadmins know about top, the standard process management and activity monitor that comes on most Linux systems. But there are times when top does not provide the information you’re really looking for, or you want something that updates more frequently as the state of your system changes.

 

Look no further than htop. It’s interactive, real-time, and sports a variety of metrics and details above and beyond what top provides.

 

You can see CPU utilization at a glance, and that’s just the tip of the iceberg. Sort processes, kill rogue jobs right from htop, and set priorities. To learn more about htop, see the htop website.

Prerequisites to Installing htop on CentOS 7

To install htop on CentOS 7, you’ll need a few things:

 

  • A CentOS 7 machine
  • Basic knowledge of Linux and how to use the shell

Installing htop on CentOS 7: Two Methods

There are two different ways you can get htop on your computer. First, you can install it as a binary from your package manager (on CentOS this would be yum). This is a good option if you want to get it right away and don’t much mind what version of htop you’re getting.

 

You can also install htop from source. Since htop is open-source, you can download the code and build it yourself on your system. This takes a little longer, but you can be sure you’re getting the most updated build available (important if you’re looking for a specific new feature).

 

We’ll go through both methods step by step.

Install htop with Yum

The yum package manager does not contain htop by default. This is okay; we just need to add an EPEL repository so yum can find it. Here’s the commands to add that repository:

 

yum -y install epel-release

yum -y update

 

Now with the repository properly added, you can tell yum to install the htop process monitoring tool:

 

yum -y install htop

If the installation completes successfully, you should be able to type htop at the command line and see the status of your system.

(source: htop screenshots)

To learn more about htop’s features and how to customize it, see the htop website or htop explained.

Install htop from Source

To ensure you have the most recent version of htop and all the new features, you can install htop from source. This involves downloading the source code and building it on your machine.

 

Installing from source means you need to gather the dependencies yourself. Before we can install htop, we’ll need Development Tools (gcc and other compilers) and ncurses.

 

yum groupinstall “Development Tools”

yum install ncurses ncurses-devel

 

With the dependencies installed, we can grab the source code and extract it:

 

wget http://hisham.hm/htop/releases/2.0.2/htop-2.0.2.tar.gz

tar xvfvz htop-2.0.2.tar.gz

cd htop-2.0.2

 

Now that we’re in the folder with the htop source code, we can run these three commands to prepare and build the code:

 

./configure

make

make install

 

Once the make install step completes, you should be able to use htop. Try typing htop into your terminal and you should see the system monitor appear.

 

If you get a htop: command not found error, you’ll need to specify the location of the htop executable in your PATH.

Conclusion: htop on CentOS7 Installed

There’s so much you can do with htop, and we hope it will help monitor your processes more quickly and easily. As always, if you have questions please leave them in the comments below.

How To Configure Varnish Cache with Apache Reverse Proxy and SSL Termination

In this guide, we will show you how to install and configure the Varnish cache for the Apache webserver with SSL termination. One limitation of Varnish Cache is that it is designed to accelerate HTTP, not the secure HTTPS protocol. Therefore, some workarounds must be performed to allow Varnish to work on SSL enabled website.

SSL/TLS Termination is the process of decrypting SSL-encrypted traffic. In our case, Apache acts like a proxy server and intermediary point between the client and Varnish and is used to convert HTTPS to HTTP.

tep 1. Install and Configure Apache (Backend) on CentOS/RHEL 8

We had CentOS 8 installed on our web server, which uses dnf package manager. However, if you are familiar with Linux systems, you can apply this manual almost entirely to other OS, such as Centos 7 (use yum) or Ubuntu and Debian (use apt instead).

1. Install Apache, start it automatically at boot, and launch

sudo dnf install httpd
sudo systemctl enable httpd
sudo systemctl start httpd
sudo systemctl status httpd

2. Create a directory for your website and grant permissions

Make sure to replace the “example.com” with your domain name:

sudo mkdir -p /var/www/example.com/public_html
sudo mkdir -p /var/www/example.com/log
sudo mkdir -p /var/www/example.com/ssl

Use aux | grep httpd or ps aux | grep apache to see what user Apache is using on your system.

In our case, the Apache user is “apache” (you may see “www-data” or other username displayed), therefore we will run the following commands to grant necessary permissions:

sudo chown -R apache:apache /var/www/
sudo chmod -R 750 /var/www

3. Create a dummy index file in your domain’s document root directory

echo 'Hello, World!' > /var/www/example.com/public_html/index.html

4. Create a new virtual host file and restart Apache

sudo mkdir /etc/httpd/sites-available
sudo mkdir /etc/httpd/sites-enabled

Tell Apache to look for virtual hosts in the sites-enabled directory:

sudo vi /etc/httpd/conf/httpd.conf

Add this line at the end of httpd.conf file:

IncludeOptional sites-enabled/*.conf

Create the new virtual host file:

sudo vi /etc/httpd/sites-available/example.com.conf
<VirtualHost *:80>
    ServerName example.com
    ServerAlias www.example.com
    DocumentRoot /var/www/example.com/public_html
    ErrorLog /var/www/example.com/error.log
    CustomLog /var/www/example.com/requests.log combined
</VirtualHost>

Enable the new virtual host files

sudo ln -s /etc/httpd/sites-available/example.com.conf /etc/httpd/sites-enabled/example.com.conf

Restart Apache

sudo systemctl restart httpd

Open access to the HTTP service in the firewall

systemctl restart firewalld
systemctl enable firewalld.service
firewall-cmd --state
firewall-cmd --zone=public --permanent --add-service=http
firewall-cmd --reload

Open your domain in the web browser to see the “Hello, World!” message, e.g.:

http://example.com or http://example.com:80

 

Step 2. Install and Configure Varnish Cache

1. Install Varnish Cache

dnf module install varnish

Change the default Varnish Listen port from 6081 to 80.

sudo vi /etc/systemd/system/varnish.service

Find the following line:

ExecStart=/usr/sbin/varnishd -a :6081 -f /etc/varnish/default.vcl -s malloc,256m

And replace it with this one:

ExecStart=/usr/sbin/varnishd -a :80 -f /etc/varnish/default.vcl -s malloc,256m

Save changes.

Check the default Varnish backend IP and port.

sudo vi /etc/varnish/default.vcl

It should look like this:

backend default {
    .host = "127.0.0.1";
    .port = "8080";
}

2. Change the default apache HTTP port 80 to 8080 (or any other port of your choice)

sudo vi /etc/httpd/conf/httpd.conf

Find the following line:

Listen 80

And replace it with this one:

Listen 8080

Save changes.

Open your virtual host file:

sudo vi /etc/httpd/sites-available/example.com.conf

Find the following line:

*:80>
ServerName example.com

And replace it with this one:

127.0.0.1:8080>
ServerName example.com

Save changes.

Launch Varnish, start it automatically at boot and check service status

varnishd -V
sudo systemctl start varnish
sudo systemctl enable varnish
sudo systemctl status varnish

Restart Apache

sudo systemctl restart httpd

Open your website in browser to see the “Hello, World!” message, e.g.:

http://example.com

Varnish cache installation and configuration process
Step 2. Diagram

Step 3. Configure Apache HTTP Server As Reverse-Proxy

1. Create SSL certificate for Apache

For the purpose of this tutorial, we will create self-signed SSL certificates. Nevertheless, you can also install free let’s encrypt certificates using this online manual.

First, you have to be sure that the mod_ssl Apache module is installed on the server.

dnf install epel-release
sudo dnf install openssl mod_ssl
sudo systemctl restart httpd

Check if mod SSL is enabled:

apachectl -M | grep ssl
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /var/www/example.com/ssl/apache-selfsigned.key -out /var/www/example.com/ssl/apache-selfsigned.crt

2. Setting up new Apache virtual host for SSL communication

Open your virtual host file:

sudo vi /etc/httpd/sites-available/example.com.conf

Add a new proxy virtual host that will listen to 443 port and redirect all traffic to Varnish (port 80), e.g. perform SSL termination.

<VirtualHost 127.0.0.1:8080>
    ServerName example.com
    ServerAlias www.example.com
    DocumentRoot /var/www/example.com/public_html
    ErrorLog /var/www/example.com/error.log
    CustomLog /var/www/example.com/requests.log combined
</VirtualHost>


<VirtualHost *:443>
    ServerName varnishtest2.plumrocket.net
    RequestHeader set X-Forwarded-Proto "https"

    ErrorLog /var/log/httpd/external-https_error.log
    CustomLog /var/log/httpd/external-https_access.log combined

    SSLEngine On
    SSLCertificateFile /etc/ssl/certs/apache-selfsigned.crt
    SSLCertificateKeyFile /etc/ssl/certs/apache-selfsigned.key

    ProxyPreserveHost On
    ProxyPass / http://127.0.0.1:80/
    ProxyPassReverse / http://127.0.0.1:80/
</VirtualHost>

Save changes and restart Apache

sudo systemctl restart httpd
Configuration of Apache HTTP Server As Reverse-Proxy
Step 3. Diagram

Step 4. Testing

Open your domain in the web browser to test if the Varnish Cache is working properly:

https://example.com

Run one of the following three commands from shell to test varnish while simultaneously refreshing the web page:

varnishlog
varnishtop
varnishstat

Enter Ctrl + C to stop the above commands from running.

If you experience any errors, it’s always wise to test each portion of our setup separately. If you look at diagram 3 above, you will see that our setup consists of 3 logical sections – Apache frontend, Varnish, and Apache backend.

Test Apache backend to see if the virtual host is accessible from the shell:

curl http://127.0.0.1:8080/

Test Varnish Cache to see if it is accessible from the shell:

curl http://127.0.0.1:80/

Finally, test the Apache frontend from the shell:

curl https://127.0.0.1/

Summary

Varnish is useful to speed up site load time and we oftentimes suggest our clients optimize their Magento store performance. Please don’t hesitate to contact us if you need assistance speeding up your Magento store. If you find this tutorial useful, please like and share it with the world.

 

Connecting Oracle database in CodeIgniter

Option 01:

$active_group = 'default';
$query_builder = TRUE;

$db['default'] = array(
    'dsn'   => '',
    'hostname' => '192.168.0.109:1521/orcl', //hostname:db_port/service_name
    //'hostname' => 'localhost:1521/orcl',
    'username' => 'db_username', 
    'password' => 'db_password', 
    'database' => 'db_name',
    'dbdriver' => 'oci8',
    'dbprefix' => '',
    'pconnect' => FALSE,
    'db_debug' => (ENVIRONMENT !== 'production'),
    'cache_on' => FALSE,
    'cachedir' => '',
    'char_set' => 'utf8',
    'dbcollat' => 'utf8_general_ci',
    'swap_pre' => '',
    'encrypt' => FALSE,
    'compress' => FALSE,
    'stricton' => FALSE,
    'failover' => array(),
    'save_queries' => TRUE
);


Option 02:

$active_group = 'default';
$active_record = TRUE;
$db['default']['hostname'] = '(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.0.246)(PORT=1521))(CONNECT_DATA=(SID=orcl)))';
$db['default']['username'] = 'db_username';
$db['default']['password'] = 'db_password';
$db['default']['database'] = 'db_name';
$db['default']['dbdriver'] = 'oci8';
$db['default']['dbprefix'] = '';
$db['default']['pconnect'] = TRUE;
$db['default']['db_debug'] = TRUE;
$db['default']['cache_on'] = FALSE;
$db['default']['cachedir'] = '';
$db['default']['char_set'] = 'utf8';
$db['default']['dbcollat'] = 'utf8_general_ci';
$db['default']['swap_pre'] = '';
$db['default']['autoinit'] = TRUE;
$db['default']['stricton'] = FALSE;

Connecting to POSTGRESQL in CodeIgniter 3

First enable Postgresql extension in php.ini

extension=php_pgsql.dll

You also can enable Postgresql extension for PDO as well.

extension=php_pdo_pgsql.dll


$db['default'] = array(
    'port'   => 5432, # Add 
);

OR

$db['default'] = array(
    'dsn'   => 'pgsql:host=localhost;port=5432;dbname=database_name', 
    'dbdriver' => 'pdo',
);
 

$active_group = ‘default’;
$query_builder = TRUE;

$db[‘default’] = array(
‘dsn’ => ”,
‘hostname’ => ‘localhost’,
‘username’ => ‘postgres’,
‘password’ => ”,
‘database’ => ‘fmsdb’,
‘dbdriver’ => ‘postgre’,
‘dbprefix’ => ”,
‘pconnect’ => FALSE,
‘db_debug’ => (ENVIRONMENT !== ‘production’),
‘cache_on’ => FALSE,
‘cachedir’ => ”,
‘char_set’ => ‘utf8’,
‘dbcollat’ => ‘utf8_general_ci’,
‘swap_pre’ => ”,
‘encrypt’ => FALSE,
‘compress’ => FALSE,
‘stricton’ => FALSE,
‘failover’ => array(),
‘save_queries’ => TRUE
);

How to install MySQL server on CentOS 8 Linux

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

How to install MySQL 8 on CentOS 8 Linux

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

Testing MySQL on CentOS 8

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

Creating MySQL 8 database with user and password on CentOS 8

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.

Install Oracle Database 19c on CentOS 8 in VirtualBox

** Please use the root user to edit the files and execute the commands unless further notice. **

Prerequisite

  1. Install the latest VirtualBox Platform Package and the VirtualBox Extension Pack (Oracle_VM_VirtualBox_Extension_Pack-VERSION.vbox-extpack).
  2. Download the latest VirtualBox Guest Additions (VBoxGuestAdditions_VERSION.iso).
  3. Download the latest CentOS Stream 8.
  4. Create a new virtual machine and install the CentOS to the virtual machine. During the CentOS installation, select Workstation as Base Environment, select Container ManagementDevelopment Tools and Graphical Administration Tools as Additional software for Selected Environment. Use http://mirror.centos.org/centos/8/BaseOS/x86_64/os/ as the installation source.
  5. After installing the CentOS, execute the following commands to get the required libraries to create applications for handling compiled objects.
dnf update
dnf -y install elfutils-libelf-devel
  1. Insert the ISO of VirtualBox Guest Additions to the virtual machine, and then install it.

Download Packages and Software

Hostname and Host File

  1. Open the file /etc/hostname, change the content to update the hostname.
ol8-19.localdomain
  1. Open the file /etc/hosts, add your IP address and hostname.
192.168.122.1 ol8-19.localdomain

Install Required Packages

  1. Perform a dnf update to update every currently installed package.
dnf update
  1. Add execute permission to the downloaded rpm files.
chmod u+x *.rpm
  1. Install the libcapl library for getting and setting POSIX.1e (formerly POSIX 6) draft 15 capabilities.
dnf localinstall -y compat-libcap1-1.10-7.el7.x86_64.rpm
  1. Inatll the libstdc++ package which contains compatibility standard C++ library from GCC 3.3.4.
dnf localinstall -y compat-libstdc++-33-3.2.3-72.el7.x86_64.rpm
  1. Install the below required packages.
dnf install -y bc binutils elfutils-libelf elfutils-libelf-devel fontconfig-devel \
    gcc gcc-c++ glibc glibc-devel ksh ksh libaio libaio-devel libgcc libnsl libnsl.i686 \
    libnsl2 libnsl2.i686 librdmacm-devel libstdc++ libstdc++-devel libX11 libXau libxcb \
    libXi libXrender libXrender-devel libXtst make net-tools nfs-utils smartmontools \
    sysstat targetcli unixODBC;

Install Oracle Installation Prerequisites

  1. Install the Oracle Installation Prerequisites (OIP) package.
dnf localinstall -y oracle-database-preinstall-19c-1.0-1.el7.x86_64.rpm
  1. Open the /etc/group file, update the GID of the below items.
oinstall:x:64890:oracle
dba:x:64891:oracle
oper:x:64892:oracle
backupdba:x:64893:oracle
dgdba:x:64894:oracle
kmdba:x:64895:oracle
racdba:x:64896:oracle
  1. Open the /etc/passwd file, update both the UID and GID of account oracle.
oracle:x:64890:64890::/home/oracle:/bin/bash
  1. Update the password of account oracle.
passwd oracle
  1. Set secure Linux to permissive by editing the /etc/selinux/config file.
SELINUX=permissive
  1. Set the secure Linux change right now.
setenforce Permissive
  1. Disable the firewall.
systemctl stop firewalld
systemctl disable firewalld

Setup Oracle User Profile

  1. Create Oracle directories.
mkdir -p /u01/app/oracle/product/19.3.0/dbhome_1
mkdir -p /u02/oradata
chown -R oracle:oinstall /u01 /u02
chmod -R 775 /u01 /u02
  1. Create a new directory for Oracle user.
mkdir -p /home/oracle/scripts
chown -R oracle:oinstall /home/oracle
  1. Create an environment setting file.
cat > /home/oracle/scripts/setEnv.sh <<EOF
# Oracle Settings
export TMP=/tmp
export TMPDIR=\$TMP

export ORACLE_HOSTNAME=$HOSTNAME
export ORACLE_UNQNAME=cdb1
export ORACLE_BASE=/u01/app/oracle
export ORACLE_HOME=\$ORACLE_BASE/product/19.3.0/dbhome_1
export ORA_INVENTORY=/u01/app/oraInventory
export ORACLE_SID=cdb1
export PDB_NAME=pdb1
export DATA_DIR=/u02/oradata

export PATH=/usr/sbin:/usr/local/bin:\$PATH
export PATH=\$ORACLE_HOME/bin:\$PATH

export LD_LIBRARY_PATH=\$ORACLE_HOME/lib:/lib:/usr/lib
export CLASSPATH=\$ORACLE_HOME/jlib:\$ORACLE_HOME/rdbms/jlib
EOF
  1. Create a startup shell script.
cat > /home/oracle/scripts/start_all.sh <<EOF
#!/bin/bash
. /home/oracle/scripts/setEnv.sh

export ORAENV_ASK=NO
. oraenv
export ORAENV_ASK=YES

dbstart \$ORACLE_HOME
EOF
  1. Create a stop shell script.
cat > /home/oracle/scripts/stop_all.sh <<EOF
#!/bin/bash
. /home/oracle/scripts/setEnv.sh

export ORAENV_ASK=NO
. oraenv
export ORAENV_ASK=YES

dbshut \$ORACLE_HOME
EOF
  1. Update the owner and permission of the shell scripts and its parent directory.
chown -R oracle:oinstall /home/oracle
chmod u+x /home/oracle/scripts/*.sh
  1. Set the environment when the Bash runs whenever it is started interactively.
cat > /home/oracle/.bashrc <<EOF
#.bashrc

# User specific aliases and functions

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Source global definitions
if [ -f /etc/bashrc ]; then
  . /etc/bashrc
fi

. /home/oracle/scripts/setEnv.sh >> /home/oracle/.bashrc
EOF

chown oracle:oinstall /home/oracle/.bashrc

Create and Add New Swap File

  1. Run the following command, with oracle user, to create and apply new swap file.
dd if=/dev/zero of=/tmp/additional-swap bs=1048576 count=4096
chmod 600 /tmp/additional-swap
mkswap /tmp/additional-swap
  1. Apply the swap by executing the following command with root user.
swapon /tmp/additional-swap

Install Oracle Database

  1. Set the DISPLAY variable with oracle user.
DISPLAY=$HOSTNAME:0.0; export DISPLAY
  1. Unzip the archive with oracle user.
cd $ORACLE_HOME
unzip -oq /path/to/software/LINUX.X64_193000_db_home.zip
  1. “Cheat” the installer about the distribution with oracle user.
export CV_ASSUME_DISTID=RHEL7.6
  1. Run the installer, with oracle user, to install Oracle database.
cd $ORACLE_HOME
./runInstaller -ignorePrereq -waitforcompletion -silent                        \
    -responseFile ${ORACLE_HOME}/install/response/db_install.rsp               \
    oracle.install.option=INSTALL_DB_SWONLY                                    \
    ORACLE_HOSTNAME=${ORACLE_HOSTNAME}                                         \
    UNIX_GROUP_NAME=oinstall                                                   \
    INVENTORY_LOCATION=${ORA_INVENTORY}                                        \
    SELECTED_LANGUAGES=en,en_GB                                                \
    ORACLE_HOME=${ORACLE_HOME}                                                 \
    ORACLE_BASE=${ORACLE_BASE}                                                 \
    oracle.install.db.InstallEdition=EE                                        \
    oracle.install.db.OSDBA_GROUP=dba                                          \
    oracle.install.db.OSBACKUPDBA_GROUP=dba                                    \
    oracle.install.db.OSDGDBA_GROUP=dba                                        \
    oracle.install.db.OSKMDBA_GROUP=dba                                        \
    oracle.install.db.OSRACDBA_GROUP=dba                                       \
    SECURITY_UPDATES_VIA_MYORACLESUPPORT=false                                 \
    DECLINE_SECURITY_UPDATES=true
  1. If the setup is success, the following message should be printed on screen.
Successfully Setup Software.
  1. Execute the below scripts, with root user, to update the permission of Oracle directories and set the environment variables.
/u01/app/oraInventory/orainstRoot.sh
/u01/app/oracle/product/19.3.0/dbhome_1/root.sh

Database Creation

  1. Start the listener with oracle user.
lsnrctl start
  1. Create a database with oracle user.
dbca -silent -createDatabase                                                   \
     -templateName General_Purpose.dbc                                         \
     -gdbname ${ORACLE_SID} -sid  ${ORACLE_SID} -responseFile NO_VALUE         \
     -characterSet AL32UTF8                                                    \
     -sysPassword SysPassword1                                                 \
     -systemPassword SysPassword1                                              \
     -createAsContainerDatabase true                                           \
     -numberOfPDBs 1                                                           \
     -pdbName ${PDB_NAME}                                                      \
     -pdbAdminPassword PdbPassword1                                            \
     -databaseType MULTIPURPOSE                                                \
     -automaticMemoryManagement false                                          \
     -totalMemory 1000                                                         \
     -storageType FS                                                           \
     -datafileDestination "${DATA_DIR}"                                        \
     -redoLogFileSize 50                                                       \
     -emConfiguration NONE                                                     \
     -ignorePreReqs

Listener Update

  1. Replace or edit the listener.ora file, with oracle user, to set the correct hostname, port number and SID name.
cat > /u01/app/oracle/product/19.3.0/dbhome_1/network/admin/listener.ora <<EOF
LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(PORT = 1539))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
  )

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = ${ORACLE_SID})
    )
  )

EOF
  1. Reload the Oracle Listener.
lsnrctl reload

Post Installation

  1. Edit the /etc/oratab file, with root user, to update the restart flag from ‘N‘ to ‘Y‘.
orcl:/u01/app/oracle/product/19.3.0/dbhome_1:Y
  1. Configure the Database instance “orcl” with auto startup.
cd $ORACLE_HOME/dbs
ln -s spfilecdb1.ora initorcl.ora
  1. Enable Oracle Managed Files (OMF) and make sure the PDB starts when the instance starts.
sqlplus / as sysdba <<EOF
alter system set db_create_file_dest='${DATA_DIR}';
alter pluggable database ${PDB_NAME} save state;
exit;
EOF
  1. Execute the following commands, with root user, to start the Oracle Listener automatically.
cat > /home/oracle/scripts/cron.sh <<EOF1
#!/bin/bash

. /home/oracle/scripts/setEnv.sh

echo "\`date\`" > /home/oracle/scripts/last.log

lsnrctl start

sleep 3

lsnrctl reload

sleep 3

sqlplus /nolog <
conn / as sysdba
startup
EOF

EOF1

chown oracle:oinstall /home/oracle/scripts/cron.sh
chmod 744 /home/oracle/scripts/cron.sh
  1. Use the following command, with oracle user, to edit the crontab file.
crontab -e
  1. Put the following cron job in the first line of crontab file, then press the keys :wq to save and exit.
@reboot /home/oracle/scripts/cron.sh

Healthcheck

  1. Login as oracle user and then execute the following commands one-by-one.
sqlplus /nolog
conn / as sysdba;
select * from v$version;
show pdbs;

Create New User and Tablespace

  1. Login as Sysdba with SqlPlus.
sqlplus / as sysdba
  1. Update the seesion setting _ORACLE_SCRIPT to true to allow common user comes without c## as prefix.
ALTER SESSION SET "_ORACLE_SCRIPT"=true;
  1. Create a new tablespace with an automatic extensible size 100MB, maximum 10G in size.
-- DROP TABLESPACE my_tablespace INCLUDING CONTENTS AND DATAFILES;
-- Location of the dat file: /u01/app/oracle/product/19.3.0/dbhome_1/dbs/my_tablespace.dat
-- SELECT tablespace_name, block_size, max_size, status FROM DBA_TABLESPACES;
CREATE TABLESPACE my_tablespace
  DATAFILE 'my_tablespace.dat'
    SIZE 100M
    AUTOEXTEND ON
    NEXT 32M MAXSIZE 10G
    EXTENT MANAGEMENT LOCAL
    SEGMENT SPACE MANAGEMENT AUTO
;

SELECT FILE_ID, FILE_NAME, TABLESPACE_NAME, AUTOEXTENSIBLE, INCREMENT_BY 
FROM DBA_DATA_FILES ORDER BY FILE_ID DESC;
  1. [Optional] Update the password life time from 180 days (default) to unlimited.
ALTER PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;
  1. Create a new user.
-- ALTER SESSION SET "_ORACLE_SCRIPT"=true;
-- DROP USER newuser CASCADE;
CREATE USER newuser IDENTIFIED BY "P@ssw0rd" DEFAULT TABLESPACE my_tablespace;
  1. Grant permissions to the new user.
-- REVOKE CREATE SESSION FROM newuser;
-- REVOKE CREATE TABLE FROM newuser;
-- REVOKE CREATE VIEW FROM newuser;
-- REVOKE CREATE ANY TRIGGER FROM newuser;
-- REVOKE CREATE ANY PROCEDURE FROM newuser;
-- REVOKE CREATE SEQUENCE FROM newuser;
-- REVOKE CREATE SYNONYM FROM newuser;
GRANT CREATE SESSION TO newuser;
GRANT CREATE TABLE TO newuser;
GRANT CREATE VIEW TO newuser;
GRANT CREATE ANY TRIGGER TO newuser;
GRANT CREATE ANY PROCEDURE TO newuser;
GRANT CREATE SEQUENCE TO newuser;
GRANT CREATE SYNONYM TO newuser;

ALTER USER newuser QUOTA UNLIMITED ON my_tablespace;
  1. [Optional] Grant DBA to the new user.
-- REVOKE DBA FROM newuser;
GRANT DBA TO newuser;

References

Free Web Hosting