Thank You for Your time and answer, Boyd: > pivot_root is supposed to do this in a way that allows you to umount > the old '/' cleanly. It is used in modern initramfs. I think I this is what I was looking for. But did You have any experience w/ it? - Works "stably"? > You can use some of the ext4 features on a existing file system by > using tune2fs to turn them on. That would eliminate the need for a > "format" and re- install. OK. Point taken.