Random servers ftp backup does not complete

A number of freepbx and piaf servers stopped saving to my IIS FTP server.

I can see the tgz file in windows explorer, 0k, then it disappears; wireshark output shows:

FTP 113 Request: STOR 20160719-000002-1468904402-935036813.tgz
FTP 108 Response: 150 Opening BINARY mode data connection.

When a server that works is able to upload, wireshark instead shows:

FTP 114 Request: STOR 20160719-000002-1468904402-1803220401.tgz
FTP 120 Response: 125 Data connection already open; Transfer starting.

I haven’t been able to find a correlation. I have a two different servers running:
asterisk 11.19.0
FreePBX 12.0.76.3
Backup and Restore Module 12.0.19

ftp settings are set to active ftp and all other settings are the same within the ftp server settings, and permissions, they both use the same user.

Any ideas???

try passive ftp

I know this is a very old post, but I still see this. Passive will not work, my ftp server is behind a firewall. My work around was to use a separate server that uses ssh and rsync (backuppc linux distro). It makes no sense to me that it works on some pbx’s and not others, and it only stopped working everywhere after I moved to a new subnet/ISP on the destination ftp server’s end. It’s not that it cannot find the FTP server–I see the traffic in a packet trace, but the servers that aren’t backing up seem to be using the wrong command to do so (150 Opening BINARY mode data connection.) and I never see the put command.