FTP 220 Service Ready vs 501 Syntax Error in Arguments
FTP 220 (Service Ready) is a 2xx Positive Completion response, while 501 (Syntax Error in Arguments) 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, 501 means that syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
Описание
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
Когда вы это видите
Immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
Как исправить
No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate.
Описание
Syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
Когда вы это видите
When you use a valid command but with wrong parameters, such as an invalid path format or incorrect argument count.
Как исправить
Review the command's required argument format. Common issues include missing quotes around paths with spaces or invalid character encoding.
Ключевые различия
220 is a 2xx Positive Completion response, while 501 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 501: Syntax error in parameters or arguments. The command was recognized but its arguments are invalid or malformed.
You encounter 220 when immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
You encounter 501 when when you use a valid command but with wrong parameters, such as an invalid path format or incorrect argument count.
Когда что использовать
For 220 (Service Ready): No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate. 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.