FTP 220 Service Ready vs 504 Parameter Not Implemented
FTP 220 (Service Ready) is a 2xx Positive Completion response, while 504 (Parameter Not Implemented) is a 5xx Permanent Negative response. 220 indicates that service ready for new user. This is the greeting message sent by the FTP server when a client first connects. In contrast, 504 means that command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
คำอธิบาย
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
เมื่อคุณพบเห็น
Immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
วิธีแก้ไข
No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate.
คำอธิบาย
Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
เมื่อคุณพบเห็น
When you use an unsupported transfer type or mode, such as TYPE E (EBCDIC) on a server that only supports ASCII and binary.
วิธีแก้ไข
Use a supported parameter value. Check the server documentation or use FEAT to see which parameter options are available.
ความแตกต่างหลัก
220 is a 2xx Positive Completion response, while 504 is a 5xx Permanent Negative response.
FTP 220: Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
FTP 504: Command not implemented for that parameter. The command is supported but not with the specific parameter value provided.
You encounter 220 when immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
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.
ควรใช้อันไหนเมื่อไร
For 220 (Service Ready): No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate. For 504 (Parameter Not Implemented): Use a supported parameter value. Check the server documentation or use FEAT to see which parameter options are available.