问php邮件中的SMTP连接错误

EN

<?php
require '/etc/PHPMailer/PHPMailerAutoload.php';

$mail = new PHPMailer(); // create a new object
$mail->IsSMTP(); // enable SMTP
$mail->SMTPDebug = 1; // debugging: 1 = errors and messages, 2 = messages only
$mail->SMTPAuth = true; // authentication enabled
$mail->SMTPSecure = 'ssl'; // secure transfer enabled REQUIRED for GMail
$mail->Host = "smtp.gmail.com";
$mail->Port = 465; // or 587
$mail->IsHTML(true);
$mail->Username = "my@gmail.com";
$mail->Password = "password";
$mail->SetFrom("from@gmail.com");
$mail->Subject = "Test";
$mail->Body = "hello";
$mail->AddAddress("to@gmail.com");
if(!$mail->Send())
{
    echo "Mailer Error: " . $mail->ErrorInfo;
}
else
{
    echo "Message has been sent";
}
?>

SMTP ERROR: Failed to connect to server: php_network_getaddresses: getaddrinfo failed: No address associated with hostname