FTP 202 Command Superfluous vs 503 Bad Sequence
FTP 202 (Command Superfluous) is a 2xx Positive Completion response, while 503 (Bad Sequence) is a 5xx Permanent Negative response. 202 indicates that the command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect. In contrast, 503 means that bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
Описание
The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
Когда вы это видите
When you send a command the server recognizes but considers unnecessary, such as ALLO on a server that does not require pre-allocation.
Как исправить
No fix needed — the server is telling you the command is not necessary. You can safely ignore this response and continue.
Описание
Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
Когда вы это видите
When you skip a required step, like sending PASS before USER, or RNTO without first sending RNFR.
Как исправить
Follow the correct command sequence. Common sequences: USER then PASS for login, RNFR then RNTO for rename, PASV then RETR for transfer.
Ключевые различия
202 is a 2xx Positive Completion response, while 503 is a 5xx Permanent Negative response.
FTP 202: The command is not implemented but is recognized as superfluous. The server acknowledges the command but it has no effect.
FTP 503: Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
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 503 when when you skip a required step, like sending PASS before USER, or RNTO without first sending RNFR.
Когда что использовать
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 503 (Bad Sequence): Follow the correct command sequence. Common sequences: USER then PASS for login, RNFR then RNTO for rename, PASV then RETR for transfer.