FTP 202 Command Superfluous vs 504 Parameter Not Implemented
FTP 202 (Command Superfluous) is a 2xx Positive Completion response, while 504 (Parameter Not Implemented) is a 5xx Permanent Negative response. 202 indicates that the command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect. In contrast, 504 means that command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
Description
The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
When You See It
When you send a command the server recognizes but considers unnecessary, such as ALLO on a server that does not require pre-allocation.
How to Fix
No fix needed — the server is telling you the command is not necessary. You can safely ignore this response and continue.
Description
Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
When You See It
When you use an unsupported transfer type or mode, such as TYPE E (EBCDIC) on a server that only supports ASCII and binary.
How to Fix
Use a supported parameter value. Check the server documentation or use FEAT to see which parameter options are available.
Key Differences
202 is a 2xx Positive Completion response, while 504 is a 5xx Permanent Negative response.
FTP 202: The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
FTP 504: Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
You encounter 202 when when you send a command the server recognizes but considers unnecessary, such as ALLO on a server that does not require pre-allocation.
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.
When to Use Which
For 202 (Command Superfluous): No fix needed — the server is telling you the command is not necessary. You can safely ignore this response and continue. For 504 (Parameter Not Implemented): Use a supported parameter value. Check the server documentation or use FEAT to see which parameter options are available.