Unable to connect ftp

A connection hung at "Retrieving directory listing…" often indicates a problem with the use of passive ports, e.g., Filezilla is trying to use passive ports, while your FTP server is not configured to accept it.

To fix it:

1. In your FTP server configuration, ensure passive ports are enabled.

2. In your FTP server configuration, define a range of ports for use as passive ports, eg. 10000-10050

3. In your firewall configuration, allow access to those ports.

This is 2018, no one should be using ftp. Switch to scp or sftp.