FTP 220 Service Ready vs 225 Data Connection Open
Both FTP 220 (Service Ready) and 225 (Data Connection Open) belong to the 2xx Positive Completion category. 220 indicates that service ready for new user. This is the greeting message sent by the FTP server when a client first connects. Meanwhile, 225 means that data connection open; no transfer in progress. The data channel is established and ready but no file transfer has started yet.
คำอธิบาย
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
เมื่อคุณพบเห็น
Immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
วิธีแก้ไข
No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate.
คำอธิบาย
Data connection open; no transfer in progress. The data channel is established and ready but no file transfer has started yet.
เมื่อคุณพบเห็น
When the data connection is established but idle, waiting for a transfer command to begin sending or receiving data.
วิธีแก้ไข
No fix needed — the data connection is ready. Issue a RETR, STOR, or LIST command to start using it.
ความแตกต่างหลัก
FTP 220: Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
FTP 225: Data connection open; no transfer in progress. The data channel is established and ready but no file transfer has started yet.
You encounter 220 when immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
You encounter 225 when when the data connection is established but idle, waiting for a transfer command to begin sending or receiving data.
ควรใช้อันไหนเมื่อไร
For 220 (Service Ready): No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate. For 225 (Data Connection Open): No fix needed — the data connection is ready. Issue a RETR, STOR, or LIST command to start using it.