Exactly how are OneDrive backups tested?

Have questions about Backup4all, or having problems using it? Ask here for help.
Post Reply
The Old Badger
Posts: 1
Joined: Thu Mar 25, 2021 4:56 pm

Exactly how are OneDrive backups tested?

Post by The Old Badger »

Hello,

From what I understand, a checksum is provided by OneDrive (personal) after a file has been uploaded.
During a backup, B4a adds files to a zip and then uploads the zip. So the checksum is for a zip file.

When a test job is carried out on the backup at a later date, exactly how does B4a determine that a file on the computer is the same as the file in the zip on OneDrive? Does B4a rebuild the original zip on the local machine and compare it to the checksum it obtained when the original zip was uploaded?

Thanks

The Old Badger

Adrian (Softland)
Posts: 1692
Joined: Wed Dec 16, 2009 12:46 pm

Re: Exactly how are OneDrive backups tested?

Post by Adrian (Softland) »

Hi,

There are two parts here:

1. The test of the backup zip is made by comparing the checksum of the uploaded zip with the checksum stored in the backup catalog (not with the source files, as they might be changed since that backup execution)

2. The source change detection is made by comparing the source files with the information stored in the backup catalog about the last file versions (multiple comparison criteria is used, as shown in Backup Properties->Advanced page)

Post Reply