FTP 120 Service Ready Soon vs 425 Can't Open Data Connection
FTP 120 (Service Ready Soon) is a 1xx Positive Preliminary response, while 425 (Can't Open Data Connection) is a 4xx Transient Negative response. 120 indicates that the service will be ready in a certain number of minutes. The server is not yet available but expects to be shortly. In contrast, 425 means that can't open data connection. The server was unable to establish the data channel needed for the file transfer.
Description
The service will be ready in a certain number of minutes. The server is not yet available but expects to be shortly.
When You See It
When connecting to an FTP server that is starting up or temporarily busy with maintenance tasks.
How to Fix
Wait the indicated number of minutes and try connecting again. If the server never becomes ready, contact the server administrator.
Description
Can't open data connection. The server was unable to establish the data channel needed for the file transfer.
When You See It
When a firewall or NAT is blocking the data connection, or the client failed to connect to the server's passive port.
How to Fix
Switch between active (PORT) and passive (PASV) modes. Check that your firewall allows the FTP data port range and that NAT is configured correctly.
Key Differences
120 is a 1xx Positive Preliminary response, while 425 is a 4xx Transient Negative response.
FTP 120: The service will be ready in a certain number of minutes. The server is not yet available but expects to be shortly.
FTP 425: Can't open data connection. The server was unable to establish the data channel needed for the file transfer.
You encounter 120 when when connecting to an FTP server that is starting up or temporarily busy with maintenance tasks.
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.
When to Use Which
For 120 (Service Ready Soon): Wait the indicated number of minutes and try connecting again. If the server never becomes ready, contact the server administrator. 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.