Duplicate increases a lot

[Skorpe]

Good, I started a few days ago to make a duplicate only of the Movies folder, it occupies 5.48 TB, the percentage of progress is 2.3% duplicated, I am surprised that it is still in process and the mirror has exceeded the space with 8.63 TB, is it normal? or is there something wrong?

 

Excuse my bad english and use translator.

[Christopher (Drashna)]

Yeah, the duplication creates multiple copies of the protected files, on other disks in the pool.  These are 1:1 copies of the files, and will take up the same amount of space as the original.

[Skorpe]

I think I saw the problem, activate more file protection, and it says that it will occupy much more, I did not read that