FTP 202 Command Superfluous vs 228 Entering Long Passive Mode
Both FTP 202 (Command Superfluous) and 228 (Entering Long Passive Mode) belong to the 2xx Positive Completion category. 202 indicates that the command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect. Meanwhile, 228 means that entering Long Passive Mode. An extended version of passive mode that supports longer addresses, including IPv6. Largely superseded by EPSV (229).
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
Entering Long Passive Mode. An extended version of passive mode that supports longer addresses, including IPv6. Largely superseded by EPSV (229).
何时出现
After issuing the LPSV command on servers that support long addresses. Rarely seen in practice as EPSV is preferred.
如何修复
No fix needed, but consider using EPSV (Extended Passive Mode) instead, which is more widely supported and simpler to parse.
主要区别
FTP 202: The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
FTP 228: Entering Long Passive Mode. An extended version of passive mode that supports longer addresses, including IPv6. Largely superseded by EPSV (229).
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 228 when after issuing the LPSV command on servers that support long addresses. Rarely seen in practice as EPSV is preferred.
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 228 (Entering Long Passive Mode): No fix needed, but consider using EPSV (Extended Passive Mode) instead, which is more widely supported and simpler to parse.