PHP实现MySQL数据库异地容灾的方法

<?php
    // 设置备份参数
    $host = "localhost";
    $user = "root";
    $pass = "password";
    $name = "database_name";
    $file = "backup.sql";
    
    // 使用mysqldump备份数据库
    $cmd = "mysqldump -h {$host} -u {$user} -p{$pass} {$name} > {$file}";
    exec($cmd);
    
    // 输出备份状态
    if (file_exists($file)) {
        echo "Backup successful!";
    } else {
        echo "Backup failed!";
    }
?>

<?php
    // 设置主数据库参数
    $master_host = "localhost";
    $master_user = "root";
    $master_pass = "password";
    $master_name = "database_name";
    
    // 设置从数据库参数
    $slave_host = "backup_ip";
    $slave_user = "root";
    $slave_pass = "password";
    $slave_name = "database_name";
    
    // 连接主数据库
    $master = new mysqli($master_host, $master_user, $master_pass, $master_name);
    if ($master->connect_error) {
        die("Connection error: " . $master->connect_error);
    }
    
    // 连接从数据库
    $slave = new mysqli($slave_host, $slave_user, $slave_pass, $slave_name);
    if ($slave->connect_error) {
        die("Connection error: " . $slave->connect_error);
    }
    
    // 设置从数据库为主数据库的从库
    $sql = "CHANGE MASTER TO master_host='{$master_host}',master_user='{$master_user}',master_password='{$master_pass}',master_log_file='mysql-bin.000001',master_log_pos=4;";
    $slave->query($sql);
    
    // 开始同步
    $sql = "START SLAVE;";
    $slave->query($sql);
?>