Settings to create backups on monthly cycle

[birney]

But .ppt files are very unlikely candidates for delta backup anyway because I believe they are not block-based. Also, 2,330 kB is a very small file to test this with. Block-level backup can work with block-based files such as database files and Outlook .PST files which are typically much larger. The log files will report if space was saved due to partial file processing or not.

a) Can you tell me more about this so I can know what to expect? Aren't all files "block-based"? If I made a modification that changed 2 blocks, why wouldn't SFFS only backup those two changed blocks (plus any necessary overhead of course)? I thought a "block-level delta" backup would compare the "current version" of a file with the "backed-up version" and just copy the blocks that it found different.

b) I created a .pst and tested with it. From the log of the test, what does this line mean?: "Remaining actual transfer amount for large files : 98.0kB"

Thank you.

[superflexible]

Aren't all files "block-based"?

On the hard disk, yes. But the applications such as Word and Powerpoint treat them as a stream of bytes. Making a small modifications may alter the whole stream and not one block on the disk stays the same as before. The whole file is written to disk every time you save it in the application. So the whole file has to be backed up again. But these files are small anyway, so it doesn't matter.

In contrast, database files including Outlook pst are accessed by the application in a block-based manner. When you make a change, only some blocks are modified on the disk.

b) I created a .pst and tested with it. From the log of the test, what does this line mean?: "Remaining actual transfer amount for large files : 98.0kB"

That is perfect. It means that only 98kB had to be backed up again because all the other blocks have not changed.