What are the best practices for handling dynamic IP addresses in PHP scripts for FTP uploads and downloads?

When dealing with dynamic IP addresses in PHP scripts for FTP uploads and downloads, it is recommended to use a domain name instead of an IP address for the FTP server. This way, you can update the domain's DNS records to point to the new IP address without having to modify the PHP script. Additionally, you can use a dynamic DNS service to automatically update the domain's IP address when it changes.

// Define the FTP server settings
$ftp_server = 'ftp.example.com';
$ftp_username = 'username';
$ftp_password = 'password';

// Connect to the FTP server
$conn_id = ftp_connect($ftp_server);

// Login to the FTP server
$login_result = ftp_login($conn_id, $ftp_username, $ftp_password);

// Perform FTP operations
// For example, uploading a file
ftp_put($conn_id, 'remote_file.txt', 'local_file.txt', FTP_ASCII);

// Close the FTP connection
ftp_close($conn_id);