FTP

FTP 215 System Type vs 425 Can't Open Data Connection

FTP 215 (System Type) is a 2xx Positive Completion response, while 425 (Can't Open Data Connection) is a 4xx Transient Negative response. 215 indicates that the NAME system type, where NAME is an official system name from the list in the Assigned Numbers document. Reports the operating system of the server. In contrast, 425 means that can't open data connection. The server was unable to establish the data channel needed for the file transfer.

คำอธิบาย

The NAME system type, where NAME is an official system name from the list in the Assigned Numbers document. Reports the operating system of the server.

เมื่อคุณพบเห็น

After issuing the SYST command. The server reports its operating system type, commonly 'UNIX Type: L8' or 'Windows_NT'.

วิธีแก้ไข

No fix needed — use this information to adjust path separators and line endings for the server's OS type.

คำอธิบาย

Can't open data connection. The server was unable to establish the data channel needed for the file transfer.

เมื่อคุณพบเห็น

When a firewall or NAT is blocking the data connection, or the client failed to connect to the server's passive port.

วิธีแก้ไข

Switch between active (PORT) and passive (PASV) modes. Check that your firewall allows the FTP data port range and that NAT is configured correctly.

ความแตกต่างหลัก

1.

215 is a 2xx Positive Completion response, while 425 is a 4xx Transient Negative response.

2.

FTP 215: The NAME system type, where NAME is an official system name from the list in the Assigned Numbers document. Reports the operating system of the server.

3.

FTP 425: Can't open data connection. The server was unable to establish the data channel needed for the file transfer.

4.

You encounter 215 when after issuing the SYST command. The server reports its operating system type, commonly 'UNIX Type: L8' or 'Windows_NT'.

5.

You encounter 425 when when a firewall or NAT is blocking the data connection, or the client failed to connect to the server's passive port.

ควรใช้อันไหนเมื่อไร

For 215 (System Type): No fix needed — use this information to adjust path separators and line endings for the server's OS type. For 425 (Can't Open Data Connection): Switch between active (PORT) and passive (PASV) modes. Check that your firewall allows the FTP data port range and that NAT is configured correctly.

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