Php operation ftp error

Hello, everyone. I have a server, (linux), which was going to test the php operation ftp, but has been unable to connect, as follows:

<?
error_reporting(E_ALL);

    $host = "XXX";
    $user = "XXX";
    $pwd = "XXX";
    $port = 2121;
    $f_conn = ftp_connect($host,2121);
    var_dump($f_conn);

return error: bool (false)

ftp_connect cannot establish a connection. I tested that other servers can connect.
it is possible to connect directly with ftp software (connection protocol: ftp), what is the situation?
php version configuration problem or firewall? Or whatever.

phpinfo:

ftp:

Php ftp linux

Mar.22,2021

you can check whether FTP is supported via phpinfo, FTP support to see if this is enabled, if it is not enabled

use ftp software to connect directly to see if ftp protocol or sftp protocol is used. If the connection is successful using sftp protocol, you cannot use the ftp_connect function.
check whether the ftp extension is installed in phpinfo
to use ftp, you must first build a ftp service on the server and use the tp_connect function to check whether the parameters are correct
here is a test code for you

<?php
// 
$conn_id = ftp_connect('116.196.116.31');
var_dump($conn_id);

?>

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MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b384eb-2c110.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b384eb-2c110.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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