WordPress site Migration from CentOS7 to Ubuntu24

Phase 1: Preparation on CentOS 7 (Source Server)

First, you need to back up your data. Log in to your CentOS server via SSH.

1、Backup the Database
Run this command to export your database to a SQL file.
(Replace db_name, db_user with your actual database details)

mysqldump -u db_user -p db_name > wordpress_backup.sql

2、Backup WordPress Files
Compress your website files into a single archive to make the transfer easier.
(Assuming your site is at /var/www/html or /usr/share/nginx/html)

tar -czf wordpress_files.tar.gz /var/www/html

Phase 2: Setup Ubuntu 24.04 (Destination Server)

Log in to your new Ubuntu 24.04 server. You need to install the LEMP stack (Linux, Nginx, MySQL, PHP).

1、Update and Install Nginx & MySQL

sudo apt update && sudo apt upgrade -y
sudo apt install nginx mysql-server ghostscript -y

2、Install PHP and Extensions
Ubuntu 24.04 defaults to PHP 8.3. Install PHP-FPM and the required WordPress extensions:

sudo apt install php-fpm php-mysql php-curl php-gd php-mbstring php-xml php-xmlrpc php-zip php-intl php-bcmath php-soap -y

3、Configure MySQL
Create a new database and user for your migrated site.

sudo mysql

Inside the MySQL shell:

CREATE DATABASE wordpress_db;
CREATE USER 'wp_user'@'localhost' IDENTIFIED BY 'strong_password';
GRANT ALL PRIVILEGES ON wordpress_db.* TO 'wp_user'@'localhost';
FLUSH PRIVILEGES;
EXIT;

Phase 3: Transfer Data

You can pull the files from your old CentOS server directly to your new Ubuntu server using rsync. Run these commands on the Ubuntu server:

(Replace root@centos_ip with your CentOS server’s user and IP)

1、Transfer the Files

rsync -avz root@centos_ip:/home/root/wordpress_files.tar.gz /tmp/
rsync -avz root@centos_ip:/home/root/wordpress_backup.sql /tmp/

Phase 4: Restore on Ubuntu 24.04

1、Restore Files
Create the web root directory and extract your files.

sudo mkdir -p /var/www/yourdomain.com
sudo tar -xzf /tmp/wordpress_files.tar.gz -C /var/www/yourdomain.com

2、Fix Permissions
CentOS often uses nginx or apache as the user, but Ubuntu uses www-data. You must update ownership:

sudo chown -R www-data:www-data /var/www/yourdomain.com
sudo find /var/www/yourdomain.com -type d -exec chmod 755 {} \;
sudo find /var/www/yourdomain.com -type f -exec chmod 644 {} \;

3、Restore Database
Import the SQL dump into the new database you created in Phase 2.

sudo mysql wordpress_db < /tmp/wordpress_backup.sql

4、Update wp-config.php
Edit your configuration file to match the new database credentials.

sudo nano /var/www/yourdomain.com/wp-config.php

Update these lines:

define( 'DB_NAME', 'wordpress_db' );
define( 'DB_USER', 'wp_user' );
define( 'DB_PASSWORD', 'strong_password' );
define( 'DB_HOST', 'localhost' );

Phase 5: Nginx Configuration

Ubuntu stores Nginx configs in /etc/nginx/sites-available/. Create a new config file:

1、Create Config File

sudo vim /etc/nginx/sites-available/yourdomain.com

2、Paste the Configuration
Note: Ubuntu 24.04 uses php8.3-fpm.sock by default. Ensure the fastcgi_pass line matches this.

server {
    listen 80;
    server_name yourdomain.com www.yourdomain.com;
    root /var/www/yourdomain.com;
    index index.php index.html index.htm;

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

    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/run/php/php8.3-fpm.sock;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
    }

    location ~ /\.ht {
        deny all;
    }
}

3、Enable the Site
Link the file to sites-enabled and test the config.

sudo ln -s /etc/nginx/sites-available/yourdomain.com /etc/nginx/sites-enabled/
sudo nginx -t

(If you see “syntax is ok”, proceed. If not, fix the errors shown).

4、Restart Nginx

sudo systemctl restart nginx

Phase 6: Final Steps

1、Update DNS: Point your domain’s A record to the new Ubuntu server’s IP address.

2、Install SSL (HTTPS): Once DNS propagates, secure your site with Let’s Encrypt.

sudo apt install certbot python3-certbot-nginx
sudo certbot --nginx -d yourdomain.com -d www.yourdomain.com

Your site should now be live on Ubuntu 24.04!