I'm running Ubuntu Server 10.04.1 and ProFTP 1.32 with a basic configuration. My server sits behind a DSL modem that is NOT running a firewall. The server has a real IP address and is not NAT'd. My home network sits behind a Linux firewall (IPFire) which also has a real IP address; workstations have private IP addresses.
I can use either the CLI or a GUI to log into the server. However, when I try to get a directory listing via CLI, I receive a "500 Illegal PORT command ftp: bind: Address already in use" error. On the GUI, as soon as the directory command is sent (MDLS) after login the connection is closed.
I've tried both enabling and disabling ephemeral ports to bypass any firewall issues, but that doesn't help.
Any insight on where the problem may be? Thanks.