Why Bareos/Bacula write label while I've already labeled it?
Because of tapes. When you write a label to tape then you need to write a whole block (about 64kB, or more when you setup a larger block size). You cant write in the middle of the block. In this block only a few hundred bytes are used. Then this kind of label is called prelabel which is overwritten during a first backup job with a label and backup stream.
