FTP 125 Data Connection Open vs 500 Syntax Error
FTP 125 (Data Connection Open) is a 1xx Positive Preliminary response, while 500 (Syntax Error) is a 5xx Permanent Negative response. 125 indicates that the data connection is already open and the transfer is beginning. No need to open a new data connection. In contrast, 500 means that syntax error, command unrecognized. The server could not parse the command. This may also be sent when the command line is too long.
説明
The data connection is already open and the transfer is beginning. No need to open a new data connection.
このコードが表示される場合
When the server reuses an existing data connection for a file transfer instead of opening a new one.
解決方法
No fix needed — the transfer is starting immediately. Your client should begin reading or writing data on the existing connection.
説明
Syntax error, command unrecognized. The server could not parse the command. This may also be sent when the command line is too long.
このコードが表示される場合
When you send a malformed or misspelled command, or a command the server does not recognize at all.
解決方法
Check the command spelling and syntax. Use HELP to see the list of supported commands on this server.
主な違い
125 is a 1xx Positive Preliminary response, while 500 is a 5xx Permanent Negative response.
FTP 125: The data connection is already open and the transfer is beginning. No need to open a new data connection.
FTP 500: Syntax error, command unrecognized. The server could not parse the command. This may also be sent when the command line is too long.
You encounter 125 when when the server reuses an existing data connection for a file transfer instead of opening a new one.
You encounter 500 when when you send a malformed or misspelled command, or a command the server does not recognize at all.
どちらをいつ使うか
For 125 (Data Connection Open): No fix needed — the transfer is starting immediately. Your client should begin reading or writing data on the existing connection. For 500 (Syntax Error): Check the command spelling and syntax. Use HELP to see the list of supported commands on this server.