FTP Kode Status
A standard protocol for transferring files between a client and server. FTP reply codes indicate the status of file transfer operations.
Lihat Spesifikasi →Tentang FTP
FTP, defined in RFC 959 (1985), is one of the oldest Internet protocols still in active use. It uses two separate channels: a control connection (port 21) for commands and replies, and a data connection (port 20 in active mode, or a negotiated port in passive mode) for file transfers. FTP reply codes are three-digit numbers: 1xx indicates a positive preliminary reply (command accepted, awaiting more), 2xx signals successful completion, 3xx means an intermediate reply requiring further input, 4xx indicates a transient negative (temporary failure, retry may succeed), and 5xx a permanent negative error. While FTP itself transmits credentials in plain text, FTPS (FTP over TLS) and SFTP (SSH File Transfer Protocol) provide encrypted alternatives. Despite the rise of HTTP-based file transfer and cloud storage, FTP remains widely used in legacy enterprise systems, web hosting, and automated batch processing.
Port bawaan: 21 · Wikipedia
100-199 1xx Positive Preliminary
The requested action is being initiated. Expect another reply before sending a new command. These indicate the command was accepted and the server is working on it.
The server is sending a restart marker reply. The text is exact and not left to interpretation. This marker is …
The service will be ready in a certain number of minutes. The server is not yet available but expects to …
The data connection is already open and the transfer is beginning. No need to open a new data connection.
The file status is okay and the server is about to open the data connection for the transfer. This is …
200-299 2xx Positive Completion
The requested action has been successfully completed. A new command may be sent.
The command has been successfully executed. This is a general acknowledgment that the command was understood and carried out.
The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
System status or system help reply. The server provides information about its current status or available features.
Directory status reply. The server provides information about the current directory or a specified directory.
File status reply. The server provides information about a specific file, typically its size or modification time.
Help message. The server provides information about its implementation status, including a list of recognized commands or help for a …
The NAME system type, where NAME is an official system name from the list in the Assigned Numbers document. Reports …
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
Service closing control connection. The server is logging out and closing the session in response to a QUIT command.
Data connection open; no transfer in progress. The data channel is established and ready but no file transfer has started …
Closing data connection. The requested file action was successful and the data connection is being closed.
Entering Passive Mode. The server provides an IP address and port number for the client to connect to for data …
Entering Long Passive Mode. An extended version of passive mode that supports longer addresses, including IPv6. Largely superseded by EPSV …
Entering Extended Passive Mode. The server provides only a port number for the data connection, using the same IP as …
User logged in, proceed. The authentication was successful and the user has full access to the FTP server.
Requested file action okay, completed. The operation on the file or directory was successful.
Pathname created. The server confirms the creation of a new directory or reports the current working directory path.
300-399 3xx Positive Intermediate
The command has been accepted but the server needs further information to complete the request. Send the additional data to proceed.
User name okay, need password. The server recognized the username and is waiting for the corresponding password to complete authentication.
Need account for login. The server requires an additional ACCT command to complete the login process, typically for account-based access …
Requested file action pending further information. The server has accepted the first part of a two-step command and is waiting …
400-499 4xx Transient Negative
The command was not accepted and the requested action did not take place. The error condition is temporary and the action may be requested again.
Service not available, closing control connection. The server is shutting down or has reached its connection limit and cannot serve …
Can't open data connection. The server was unable to establish the data channel needed for the file transfer.
Connection closed; transfer aborted. The data connection was closed unexpectedly during a file transfer.
Requested file action not taken. The file is unavailable due to being busy, locked by another process, or temporarily inaccessible.
Requested action aborted: local error in processing. The server encountered an unexpected error while trying to complete the command.
Requested action not taken. Insufficient storage space in system. The server ran out of disk space while processing the command.
500-599 5xx Permanent Negative
The command was not accepted and the requested action did not take place. The error is permanent and the same command should not be retried without changes.
Syntax error, command unrecognized. The server could not parse the command. This may also be sent when the command line …
Syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
Command not implemented. The server recognizes the command but does not support it in its current configuration.
Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
Not logged in. The user is not authenticated and must log in before the requested command can be executed.
Need account for storing files. The server requires an ACCT command before it will allow file uploads, even though the …
Requested action not taken. File unavailable — the file does not exist, the path is wrong, or you do not …
Requested action aborted: page type unknown. The server does not recognize the requested page structure or format.
Requested file action aborted. Exceeded storage allocation for the current directory or dataset. The user's quota has been reached.
Requested action not taken. File name not allowed. The file or directory name violates the server's naming rules or filesystem …
Panduan FTP
A practical guide to FTP reply codes — from successful transfers (226) to login failures (530) and permission denied (550).
TCP Three-Way Handshake and Connection LifecycleHow TCP connections are established, maintained, and torn down — SYN/SYN-ACK/ACK, window scaling, keep-alive, TIME_WAIT, and tcpdump analysis.
Essential Network Debugging Tools: ping, traceroute, mtr, and tcpdumpPractical guide to command-line network diagnostic tools — when to use each, how to interpret output, and common patterns for …
RFC 959: FTP Protocol Deep DiveUnderstanding the File Transfer Protocol — command/response model, active vs passive mode, ASCII vs binary transfer types, and why FTP …
TLS 1.3: Faster, Simpler, More SecureHow TLS 1.3 reduced handshake latency (1-RTT/0-RTT), removed insecure ciphers, and simplified the protocol — comparison with TLS 1.2 and …
Migrating from FTP to SFTP: A Complete Transition GuideHow to replace insecure FTP with SFTP (SSH File Transfer Protocol) — server setup, client configuration, automation scripts, and legacy …