Problems with Transfers to and from FTP Sites

A common reason that a transfer fails is that the FTP server is not accessible from the application server. This error could be due to:

  • An incorrect password.

  • An incorrect account name.

  • An inability of the application server to resolve the FTP server's host name.

  • The FTP server is down.

Try to ping the FTP server machine from the application server system, and then try to manually transfer a file to the FTP server machine from the application server.

If the FTP site is on Microsoft Windows, the host name for the system might not be associated with a fixed IP address and might not be resolvable using DNS (Domain Name System). If the application server is on a UNIX machine, the application server can resolve the host name using DNS only—or perhaps using NIS (Network Information System) or an /etc/hosts file. However, the application server will be unable to use Windows mechanisms such as WinBeui or WINS. Therefore, the application server will not be able to convert the host name indicated for the Microsoft Windows file server into an IP address and route to it.

If the file transfer fails, you must resolve the problem by either specifying the numeric IP address in the FTP URL or by putting the host name for the FTP site into DNS, NIS, or the hosts file on your application server so that the name can be resolved.

Typically, the URL used for file attachments has the following format:

ftp://user:pwd@system_name/dir1/subdir

However, if the domain name cannot be resolved with DNS, then use the numeric IP address. The following example assumes system_name has the IP address of 192.0.2.1: 

ftp://user:pwd@192.0.2.1/dir1/subdir

Note:

Use numeric IP addresses only when absolutely necessary.