If <filename>/boot/loader</filename> fails to load, but the primary bootstrap still loads (visible by a single dash in the left column of the screen right after the boot process starts), an attempt can be made to interrupt the primary bootstrap by pressing <keycap>space</keycap>. This will make the bootstrap stop in <link xlink:href="@@URL_RELPREFIX@@/doc/en_US.ISO8859-1/books/handbook/boot.html#boot-boot1">stage two</link>. An attempt can be made here to boot off an alternate partition, like the partition containing the previous root file system that has been moved away from <literal>a</literal>.