FTP 200 Command OK vs 503 Bad Sequence
FTP 200 (Command OK) is a 2xx Positive Completion response, while 503 (Bad Sequence) is a 5xx Permanent Negative response. 200 indicates that the command has been successfully executed. This is a general acknowledgment that the command was understood and carried out. In contrast, 503 means that bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
描述
The command has been successfully executed. This is a general acknowledgment that the command was understood and carried out.
何时出现
After issuing any command that completes successfully, such as TYPE, MODE, or NOOP.
如何修复
No fix needed — the command succeeded. This is the standard positive response for commands that don't return data.
描述
Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
何时出现
When you skip a required step, like sending PASS before USER, or RNTO without first sending RNFR.
如何修复
Follow the correct command sequence. Common sequences: USER then PASS for login, RNFR then RNTO for rename, PASV then RETR for transfer.
主要区别
200 is a 2xx Positive Completion response, while 503 is a 5xx Permanent Negative response.
FTP 200: The command has been successfully executed. This is a general acknowledgment that the command was understood and carried out.
FTP 503: Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
You encounter 200 when after issuing any command that completes successfully, such as TYPE, MODE, or NOOP.
You encounter 503 when when you skip a required step, like sending PASS before USER, or RNTO without first sending RNFR.
何时使用哪个
For 200 (Command OK): No fix needed — the command succeeded. This is the standard positive response for commands that don't return data. 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.