You should always test your FTP installation by attempting to use an FTP client to log into your FTP server to transfer sample files.
The most common sources of day-to-day failures are incorrect usernames and passwords.
Initial setup failures could be caused by firewalls along the path between the client and server blocking some or all types of FTP traffic. Typical symptoms of this are either connection timeouts or the ability to use the ls command to view the contents of a directory without the ability to either upload or download files. Follow the firewall rule guidelines to help overcome this problem. Connection problems could also be the result of typical network issues outlined in Chapter 4, "Simple Network Troubleshooting."