FTP 220 Service Ready vs 426 Connection Closed
FTP 220 (Service Ready) is a 2xx Positive Completion response, while 426 (Connection Closed) is a 4xx Transient Negative response. 220 indicates that service ready for new user. This is the greeting message sent by the FTP server when a client first connects. In contrast, 426 means that connection closed; transfer aborted. The data connection was closed unexpectedly during a file transfer.
설명
Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
이 코드를 보게 되는 경우
Immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
해결 방법
No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate.
설명
Connection closed; transfer aborted. The data connection was closed unexpectedly during a file transfer.
이 코드를 보게 되는 경우
When a file transfer is interrupted due to a network timeout, client disconnect, or the data connection dropping mid-transfer.
해결 방법
Retry the transfer. If it keeps failing, check network stability, increase timeout values, and verify there are no firewalls killing idle connections.
주요 차이점
220 is a 2xx Positive Completion response, while 426 is a 4xx Transient Negative response.
FTP 220: Service ready for new user. This is the greeting message sent by the FTP server when a client first connects.
FTP 426: Connection closed; transfer aborted. The data connection was closed unexpectedly during a file transfer.
You encounter 220 when immediately upon connecting to an FTP server. This is the welcome banner confirming the server is accepting connections.
You encounter 426 when when a file transfer is interrupted due to a network timeout, client disconnect, or the data connection dropping mid-transfer.
언제 어떤 것을 사용할지
For 220 (Service Ready): No fix needed — the server is ready. Proceed with USER and PASS commands to authenticate. For 426 (Connection Closed): Retry the transfer. If it keeps failing, check network stability, increase timeout values, and verify there are no firewalls killing idle connections.