F-SECURE INTERNET GATEKEEPER FOR LINUX 4.01 Administrator's Manual page 159

④ If the connection fails:
1) The following is sent to the client: -500 Can't Connect to (Server host: Server port)
errmsg=[Connection error message]
For connection error messages, see
", 162.
⑤ The following is sent to the server: USER [User name]
⑥ Receives a response from the server.
⑦ The following is sent to the client: [Server response information]
QUIT command
1 If connected to a server:
① The following is sent to the server: [Client response information]
② Receives a response from the server.
③ The following is sent to the client: [Server response information]
2 If (2) above does not apply:
① The following is sent to the client: 221 Quit
PASV command
1 The following is sent to the server: PASV
2 Receives a response from the server.
3 The following is sent to the client: 227 Entering Passive Mode (xx,xx,xx,xx,yy,yy)
(xx is the IP address of the proxy and yy is the proxy port)
PORT command
1 The following is sent to the client: PORT (xx,xx,xx,xx,yy,yy)
(xx is the IP address of the proxy and yy is the proxy port)
2 Receives a response from the server.
3 The following is sent to the client: [Server response information]
RETR/LIST/NLST/STOR/STOU/APPE commands
1 If PASV/PORT commands are not executed:
① The following is sent to the client: 530 please use PORT/PASV command at first.
② The command terminates.
2 If the mode is PASV:
① Waits for a data session to connect.
② If the source of the data session and control session are different:
1) The following is sent to the client: 530 Invalid Connection Source.
2) The command terminates.
③ Connects to the server with the data session.
④ Receives a response from the server.
⑤ The following is sent to the client: Server response information
⑥ If the response code is other than 1xx:
1) The command terminates.
F-Secure Internet Gatekeeper for Linux/Administrator's Guide
"Connection Error Messages
159