FTP 220 Service Ready vs 551 Page Type Unknown
FTP 220 (Service Ready) is a 2xx Positive Completion response, while 551 (Page Type Unknown) 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, 551 means that requested action aborted: page type unknown. The server does not recognize the requested page structure or format.
Açıklama
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
Gördüğünüzde
Immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
Nasıl Düzeltilir
No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate.
Açıklama
Requested action aborted: page type unknown. The server does not recognize the requested page structure or format.
Gördüğünüzde
When attempting a transfer with a page structure type the server does not support. This is extremely rare in modern FTP usage.
Nasıl Düzeltilir
Switch to stream transfer mode (MODE S) and file structure (STRU F), which are universally supported by all FTP servers.
Temel Farklar
220 is a 2xx Positive Completion response, while 551 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 551: Requested action aborted: page type unknown. The server does not recognize the requested page structure or format.
You encounter 220 when immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
You encounter 551 when when attempting a transfer with a page structure type the server does not support. This is extremely rare in modern FTP usage.
Hangisini Ne Zaman Kullanmalı
For 220 (Service Ready): No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate. For 551 (Page Type Unknown): Switch to stream transfer mode (MODE S) and file structure (STRU F), which are universally supported by all FTP servers.