FTP 125 Data Connection Open vs 530 Not Logged In
FTP 125 (Data Connection Open) is a 1xx Positive Preliminary response, while 530 (Not Logged In) is a 5xx Permanent Negative response. 125 indicates that the data connection is already open and the transfer is beginning. No need to open a new data connection. In contrast, 530 means that not logged in. The user is not authenticated and must log in before the requested command can be executed.
描述
The data connection is already open and the transfer is beginning. No need to open a new data connection.
何时出现
When the server reuses an existing data connection for a file transfer instead of opening a new one.
如何修复
No fix needed — the transfer is starting immediately. Your client should begin reading or writing data on the existing connection.
描述
Not logged in. The user is not authenticated and must log in before the requested command can be executed.
何时出现
When you try to access files or run commands before authenticating, or after providing incorrect login credentials.
如何修复
Send USER and PASS commands with valid credentials. If login fails repeatedly, verify the username, password, and check if the account is locked.
主要区别
125 is a 1xx Positive Preliminary response, while 530 is a 5xx Permanent Negative response.
FTP 125: The data connection is already open and the transfer is beginning. No need to open a new data connection.
FTP 530: Not logged in. The user is not authenticated and must log in before the requested command can be executed.
You encounter 125 when when the server reuses an existing data connection for a file transfer instead of opening a new one.
You encounter 530 when when you try to access files or run commands before authenticating, or after providing incorrect login credentials.
何时使用哪个
For 125 (Data Connection Open): No fix needed — the transfer is starting immediately. Your client should begin reading or writing data on the existing connection. For 530 (Not Logged In): Send USER and PASS commands with valid credentials. If login fails repeatedly, verify the username, password, and check if the account is locked.