FTP 110 Restart Marker Reply vs 227 Entering Passive Mode
FTP 110 (Restart Marker Reply) is a 1xx Positive Preliminary response, while 227 (Entering Passive Mode) is a 2xx Positive Completion response. 110 indicates that the server is sending a restart marker reply. The text is exact and not left to interpretation. This marker is used to indicate the point at which a file transfer should be restarted. In contrast, 227 means that entering Passive Mode. The server provides an IP address and port number for the client to connect to for data transfer, formatted as (h1,h2,h3,h4,p1,p2).
Description
The server is sending a restart marker reply. The text is exact and not left to interpretation. This marker is used to indicate the point at which a file transfer should be restarted.
When You See It
During a resumed file transfer when the server confirms the restart position in the data stream.
How to Fix
No fix needed — this is a normal response during transfer recovery. If restarts keep failing, verify the marker format matches what your client expects.
Description
Entering Passive Mode. The server provides an IP address and port number for the client to connect to for data transfer, formatted as (h1,h2,h3,h4,p1,p2).
When You See It
After issuing the PASV command. The server switches to passive mode and tells the client where to connect for data transfer.
How to Fix
No fix needed — parse the IP and port from the response to establish the data connection. If connections fail, check NAT/firewall rules on the passive port range.
Key Differences
110 is a 1xx Positive Preliminary response, while 227 is a 2xx Positive Completion response.
FTP 110: The server is sending a restart marker reply. The text is exact and not left to interpretation. This marker is used to indicate the point at which a file transfer should be restarted.
FTP 227: Entering Passive Mode. The server provides an IP address and port number for the client to connect to for data transfer, formatted as (h1,h2,h3,h4,p1,p2).
You encounter 110 when during a resumed file transfer when the server confirms the restart position in the data stream.
You encounter 227 when after issuing the PASV command. The server switches to passive mode and tells the client where to connect for data transfer.
When to Use Which
For 110 (Restart Marker Reply): No fix needed — this is a normal response during transfer recovery. If restarts keep failing, verify the marker format matches what your client expects. For 227 (Entering Passive Mode): No fix needed — parse the IP and port from the response to establish the data connection. If connections fail, check NAT/firewall rules on the passive port range.