FTP 202 Command Superfluous vs 501 Syntax Error in Arguments
FTP 202 (Command Superfluous) is a 2xx Positive Completion response, while 501 (Syntax Error in Arguments) 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, 501 means that syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
描述
The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
何时出现
When you send a command the server recognizes but considers unnecessary, such as ALLO on a server that does not require pre-allocation.
如何修复
No fix needed — the server is telling you the command is not necessary. You can safely ignore this response and continue.
描述
Syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
何时出现
When you use a valid command but with wrong parameters, such as an invalid path format or incorrect argument count.
如何修复
Review the command's required argument format. Common issues include missing quotes around paths with spaces or invalid character encoding.
主要区别
202 is a 2xx Positive Completion response, while 501 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 501: Syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
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 501 when when you use a valid command but with wrong parameters, such as an invalid path format or incorrect argument count.
何时使用哪个
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 501 (Syntax Error in Arguments): Review the command's required argument format. Common issues include missing quotes around paths with spaces or invalid character encoding.