Sybase DC38133-01-0902-01 manual Troubleshooting ftp problems

Chapter 10. SQL Remote Administration

♦port Usually not required. This is the IP port number used for the Ftp connection.

♦debug This is set to either YES or NO, with the default being NO. When set to YES, debugging output is displayed.

♦active_mode This is set to either YES or NO, with the default being NO (passive mode).

Troubleshooting ftp problems

Most problems with the FTP message link are network setup issues. This section contains a list of tests you can try to troubleshoot problems.

Set the DEBUG message control parameter Looking over the debug output should indicate whether you are connecting to the FTP server. If you are connecting, it will indicate which FTP commands are failing.

Ping the ftp server If the FTP link is not able to connect to the FTP server, try testing your systems network configuration. If your system has the ping command, try typing the following command:

ping ftp-server-name

You should see output indicating the IP address of the server and the ping (round trip) time to the server. If you can not ping the server than you have a network configuration problem, and you should contact you network administrator.

Check that passive mode works If the FTP link is connecting to the FTP server, but is unable to open a data connection, make sure that an FTP client can use passive mode to transfer data with the server.

Passive mode is the preferred transfer mode and the default for the FTP message link. In passive mode all data transfer connections are initiated by the client, in this case the message link. In Active mode the server initiates all data connections. If your FTP server is sitting behind an incorrectly configured firewall you may not be able to use the default passive transfer mode. In this situation the firewall blocks socket connections to the FTP server on ports other than the FTP control port.

Using an FTP user program that allows you to set the transfer mode between active and passive, set the transfer mode to passive and try to upload/download a file. If the client you are using cannot transfer the file without using active mode than you should either reconfigure the firewall and FTP server to allow passive mode transfers or set the active_mode message control parameter to YES. Active mode transfers may not work in all network configurations. For example: if your client is sitting behind an IP

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