I know some files are bound to be growing when I back them up. In this case, this is an oracle database file and I'm only testing. When I put amanda in place for good, I will stop oracle and move the database files somewhere else before backing them up, and exclude the "live" files.
But for other type of files: ex: web server logs, will the "partly" backed up file be restorable ? I know I'm gonna miss the "end of it" (it is written sequentially) but will it be resotrable ? When errors/warnings of this type happen, is the tape still usable ? Thanks