FTP 125 Data Connection Open vs 504 Parameter Not Implemented
FTP 125 (Data Connection Open) is a 1xx Positive Preliminary response, while 504 (Parameter Not Implemented) 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, 504 means that command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
Описание
The data connection is already open and the transfer is beginning. No need to open a new data connection.
Когда вы это видите
When the server reuses an existing data connection for a file transfer instead of opening a new one.
Как исправить
No fix needed — the transfer is starting immediately. Your client should begin reading or writing data on the existing connection.
Описание
Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
Когда вы это видите
When you use an unsupported transfer type or mode, such as TYPE E (EBCDIC) on a server that only supports ASCII and binary.
Как исправить
Use a supported parameter value. Check the server documentation or use FEAT to see which parameter options are available.
Ключевые различия
125 is a 1xx Positive Preliminary response, while 504 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 504: Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
You encounter 125 when when the server reuses an existing data connection for a file transfer instead of opening a new one.
You encounter 504 when when you use an unsupported transfer type or mode, such as TYPE E (EBCDIC) on a server that only supports ASCII and binary.
Когда что использовать
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 504 (Parameter Not Implemented): Use a supported parameter value. Check the server documentation or use FEAT to see which parameter options are available.