Just wondering if this is expected behaviour or not. We've recently backed up three of our scanning appliances (11.2 CentOS 6) via SSH to a backup server, the estimated backup size for each of them was roughly 150gb but the actual size of each backup file ended up being somewhere around 30/40gb of disk space. We had Verify backup, Include sensitive data, Encrypt Backup set to on. And Reduce backup size set to off.
I understand there could be some compression when it comes to the encryption / backup process, but I wouldn't have expected such a decrease, especially with the Reduce backup size option set to off.
It can get quite a bit smaller as normally discovery contains a limited set of ASCII characters which will compress significantly.