FTP 220 Service Ready vs 228 Entering Long Passive Mode
Both FTP 220 (Service Ready) and 228 (Entering Long Passive Mode) belong to the 2xx Positive Completion category. 220 indicates that service ready for new user. This is the greeting message sent by the FTP server when a client first connects. 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 Largely superseded by EPSV (229).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
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
何时出现
Immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
如何修复
No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate.
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 Largely superseded by EPSV (229).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 220: Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
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 Largely superseded by EPSV (229).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 220 when immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
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 220 (Service Ready): No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate. 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.