Steps to Enable MySQLi Extension

Update Package Lists:

Before proceeding, ensure your package lists are up to date:

sudo apt-get update

Install MySQLi Extension:

Install the MySQLi PHP extension if it's not already installed:

sudo apt-get install php-mysqli

Restart Apache:

After installing the extension, restart Apache to apply the changes:

sudo systemctl restart apache2

Verify MySQLi Extension:

You can verify if the MySQLi extension is enabled by creating a PHP file in your web server's root directory (/var/www/html by default) with the following content:

php

<?php

phpinfo();

?>

Save the file (e.g., info.php) and access it through your web browser (e.g., http://your-ec2-instance-public-dns/info.php). Look for a section named "mysqli" in the PHP info page to confirm that the extension is enabled.

Configure phpMyAdmin:

If you still encounter issues after enabling the MySQLi extension, you may need to reconfigure phpMyAdmin to recognize the extension. Use the following command to reconfigure phpMyAdmin:

sudo dpkg-reconfigure phpmyadmin

Follow the prompts and ensure that during the configuration, the MySQLi extension is selected and enabled.

Resolving MySQL Password Policy Error

To resolve this issue, you have a few options:

Choose a Stronger Password:

MySQL has password strength requirements. Make sure your chosen password meets these requirements, such as having a mix of uppercase and lowercase letters, numbers, and special characters.

Change MySQL Password Policy:

If you have control over MySQL's configuration and are willing to adjust its password policy, you can lower the password validation level. However, this might not be recommended for security reasons.

Retry with a Different Password:

Retry the installation with a different password that meets the MySQL password policy requirements.

Steps to Retry Installation

Retry the Installation:

Choose the option to retry installation when prompted. During this retry, make sure to enter a password that complies with MySQL's password policy.

sudo dpkg-reconfigure phpmyadmin

Follow the prompts and when asked to set up the MySQL application password, enter a strong password that satisfies MySQL's password policy requirements.

Manually Configure phpMyAdmin:

Alternatively, you can skip the automatic database setup during phpMyAdmin installation and manually configure it later. This involves setting up a MySQL database and user separately.

sudo dpkg-reconfigure phpmyadmin

During the configuration process, choose the manual configuration option when prompted.

Example Commands to Execute

Here's an example of how you might retry the installation and set a password:

sudo dpkg-reconfigure phpmyadmin

Follow the prompts and ensure to provide a password that meets MySQL's password policy requirements when prompted.

Step-by-Step Guide

Wait for the Current Process to Complete

Sometimes, the best approach is to wait a few minutes for the current process to complete. If the issue persists, proceed with the following steps.

Identify the Process Holding the Lock

Identify the process holding the lock and see if it is still active:

sudo lsof /var/lib/dpkg/lock

This will show you the process that is currently using the lock. Alternatively, you can use the ps command:

ps aux | grep dpkg

Terminate the Process (if necessary)

If you determine that the process is not performing any critical operations or it is stuck, you can terminate it. Replace PID with the process ID you found in the previous step:

sudo kill -9 PID

Remove the Lock Files

After terminating the process, you can safely remove the lock files:

sudo rm /var/lib/dpkg/lock

sudo rm /var/lib/dpkg/lock-frontend

sudo rm /var/cache/apt/archives/lock

Reconfigure dpkg

Sometimes, dpkg can be left in an inconsistent state. Running the following command can fix this:

sudo dpkg --configure -a

Update and Install Packages Again

Now you should be able to update your package list and install packages without issues:

sudo apt-get update

sudo apt-get install php7.4-mysqli