Tools

421 FTP response code in Serv-U

A 421 response code indicates that while the service is still running, the service is unavailable at the time of connection. It indicates that the server will be restarting as soon as it finishes processing pending operations (usually any file transfers currently in progress). It is considered a transient negative response, which means the client is encouraged to issue the same command again at a later time when it can be accepted.

First published date

10/25/2018 6:47 PM

Last published date

11/12/2019 9:42 AM

Overview

This article provides information on 421 FTP response code.

Product section

Serv-U Managed File Transfer & Serv-U FTP Server

Resolution

A 421 response code indicates that while the service is still running, the service is unavailable at the time of connection. It indicates that the server will be restarting as soon as it finishes processing pending operations (usually any file transfers currently in progress). It is considered a transient negative response, which means the client is encouraged to issue the same command again at a later time when it can be accepted.

Example response 

421 Service not available, closing control connection.

Possible commands 

421 FTP response code may be given in response to any FTP command or connection attempt if the FTP server knows it must shut down.