FTP 202 Command Superfluous vs 451 Local Error
FTP 202 (Command Superfluous) is a 2xx Positive Completion response, while 451 (Local Error) is a 4xx Transient 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, 451 means that requested action aborted: local error in processing. The server encountered an unexpected error while trying to complete the command.
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
Requested action aborted: local error in processing. The server encountered an unexpected error while trying to complete the command.
何时出现
When the server has an internal issue like a disk I/O error, memory shortage, or filesystem problem during command processing.
如何修复
Retry the command. If the error persists, contact the server administrator to check disk health, available memory, and server logs.
主要区别
202 is a 2xx Positive Completion response, while 451 is a 4xx Transient 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 451: Requested action aborted: local error in processing. The server encountered an unexpected error while trying to complete the command.
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 451 when when the server has an internal issue like a disk I/O error, memory shortage, or filesystem problem during command processing.
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 451 (Local Error): Retry the command. If the error persists, contact the server administrator to check disk health, available memory, and server logs.