completely erase and reinstall mysql script.

 Warning: this will delete ALL your databases.

After running this script it will let you automatically run mysql without a password (as root). Note this  is a security risk so do not run this on a production server.

#!/bin/bash

set -e

# Function to remove MySQL and clean up
remove_mysql() {
    echo "Removing MySQL server and packages..."
    sudo apt-get remove -y mysql-server mysql-client mysql-common

    echo "Removing MySQL directories..."
    sudo rm -rf /etc/mysql /var/lib/mysql /var/log/mysql /var/run/mysqld

    # Clean up any residual packages and update package info
    sudo apt-get autoremove -y
    sudo apt-get clean
}

# Function to ensure MySQL configuration file exists
ensure_mysql_config() {
    if [ ! -f /etc/mysql/mysql.cnf ]; then
        echo "Creating MySQL configuration file..."
        echo "[client]" | sudo tee /etc/mysql/mysql.cnf
        echo "user=root" | sudo tee -a /etc/mysql/mysql.cnf
        echo "password=abcd1234*" | sudo tee -a /etc/mysql/mysql.cnf
        echo "MySQL configuration file created at /etc/mysql/mysql.cnf."
    fi
}

# Function to create .my.cnf files in user directories
create_user_mysql_config() {
    echo "Configuring MySQL client for all users..."
    for home in /home/*; do
        if [ -d "$home" ]; then
            user=$(basename "$home")
            echo "[client]" > "$home/.my.cnf"
            echo "user=root" >> "$home/.my.cnf"
            echo "password=abcd1234*" >> "$home/.my.cnf"
            chown "$user:$user" "$home/.my.cnf"
            chmod 600 "$home/.my.cnf"
            su -c "mysql_config_editor set --host=localhost --user=root --password" -s /bin/bash "$user"
        fi
    done
}

is_running() {
echo "Checking MySQL service status..."
    if ! sudo systemctl is-active --quiet mysql; then
        sudo systemctl stop mysql
    fi
}

# Function to reinstall and configure MySQL
reinstall_mysql() {
    echo "Reinstalling MySQL server and client..."
    sudo apt-get update
    sudo apt-get install -y mysql-server mysql-client mysql-common

    # Ensure necessary MySQL configuration directories and files
    echo "Ensuring MySQL configuration files and directories..."
    sudo mkdir -p /etc/mysql /var/lib/mysql /var/log/mysql /var/run/mysqld
    sudo chown -R mysql:mysql /var/lib/mysql /var/run/mysqld
    sudo chmod 755 /var/run/mysqld

    echo "Ensure MySQL configuration file"
    ensure_mysql_config

    echo "Fixing broken packages and reconfiguring..."
    sudo dpkg --configure -a
    sudo apt-get install -f
}

# Function to reset MySQL root password
reset_mysql_password() {
    echo "Resetting MySQL root password..."

    # Ensure the MySQL directory for socket exists
    sudo mkdir -p /var/run/mysqld
    sudo chown mysql:mysql /var/run/mysqld
    sudo chmod 755 /var/run/mysqld

    # Start MySQL with --skip-grant-tables in the background
    sudo echo "ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'abcd1234*'; FLUSH PRIVILEGES;" > /var/lib/mysql/reset.txt

sudo chown mysql:mysql /var/run/mysqld
sudo chmod 777 /var/run/mysqld # you can make this 755 some other time
sudo mysqld --init-file=/var/lib/mysql/reset.txt  --user=mysql

    # Start MySQL normally
    sudo systemctl restart mysql
}

# Main script logic
echo "Do you want to remove MySQL packages and directories? (y/n): "
read answer

if [ "$answer" = "y" ] || [ "$answer" = "Y" ]; then
    remove_mysql
fi

is_running
create_user_mysql_config
ensure_mysql_config
reinstall_mysql
reset_mysql_password

echo "MySQL has been reinstalled (if needed), root password has been reset, and client configuration is updated for all users."

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