How to set up (and recover) Vicidial audio recording conversion and FTP to an archive server.

I have a large volume customer with a Vicidial cluster that I set up to convert call recordings to MP3 format and FTP them to an archive server where they are cataloged and accessible via a lookup tool. Everything was working great until their FTP server went down and they didn't realize it for 14 days. This post outlines how to set up audio conversion and FTP, and what was done to get the 14 days of recordings moved over to the archive server.