FTP 211 System Status vs 503 Bad Sequence
FTP 211 (System Status) is a 2xx Positive Completion response, while 503 (Bad Sequence) is a 5xx Permanent Negative response. 211 indicates that system status or system help reply. The server provides information about its current status or available features. In contrast, 503 means that bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
Description
System status or system help reply. The server provides information about its current status or available features.
When You See It
After issuing the STAT command without arguments, the server returns its system status and supported features.
How to Fix
No fix needed — this is an informational response. Use the information to understand the server's capabilities and current state.
Description
Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
When You See It
When you skip a required step, like sending PASS before USER, or RNTO without first sending RNFR.
How to Fix
Follow the correct command sequence. Common sequences: USER then PASS for login, RNFR then RNTO for rename, PASV then RETR for transfer.
Key Differences
211 is a 2xx Positive Completion response, while 503 is a 5xx Permanent Negative response.
FTP 211: System status or system help reply. The server provides information about its current status or available features.
FTP 503: Bad sequence of commands. The command is valid but was sent in the wrong order relative to other commands.
You encounter 211 when after issuing the STAT command without arguments, the server returns its system status and supported features.
You encounter 503 when when you skip a required step, like sending PASS before USER, or RNTO without first sending RNFR.
When to Use Which
For 211 (System Status): No fix needed — this is an informational response. Use the information to understand the server's capabilities and current state. 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.