How does the backup process work?

[Pagemakers]

Does the server backup process work like this..

1. Create the backup
2. Place in the server repository
3. Transfer the file to the FTP server
4. Delete the old backup from FTP server
5. Delete the temp backup for the server repository

I'm not sure about point 4 or if indeed this process is correct at all.

The problem I am having is my server backup keeps failing. It transfers 79G out of 83G to the FTP server.

I get the error. Can't upload file 'backup_info_1511080326.xml' to ftp. Error code: 1

I have 88G free on the backup server after the backup finishes.

I am wondering in point 3 above is a complete 2nd backup made before the first backup is deleted? This may explain the failures, of other domain backups are happening at the same time.

If I delete the old backup and start fresh, it works fine.