Booting without an image

On Wed, 03 May 2006 23:20:13 GMT, James S. Singleton staggered into the Black Sun and said:

OSes give you a great deal of rope to hang yourself with, as you will find out. (OTOH, making Stupid Mistakes when you're a newbie is par for the course.)

LILO, unlike GRUB, doesn't read the filesystem. This explanation is incomplete and may contain errors, corrections from someone who's actually used LILO in the last 4 years welcome:

When you run LILO, it reads the filesystem and finds where all the image= files live. It then writes a list of the blocks where those image files are to the map file (usually given by the map= statement in lilo.conf, unless they've changed that in the last 4 years.) The map file's starting block is written to an absolute point somewhere. This way, LILO only needs to read a few blocks from absolute block positions, which makes LILO simpler than GRUB.

This makes it possible for LILO's critical information to survive a mkfs. mkfs doesn't erase every block, just the things it needs to erase to create a new filesystem--that usually means the superblock and the block bitmaps. Files that were on the old filesystem are still there in the same absolute positions. Well, they'll be there until you write some new data to this filesystem, at which point they may or may have random parts of themselves overwritten by your new data.

LILO will complain about not finding some files inboot . I forget exactly what they're called, but it won't run. You need to copy the needed files over toboot ; your kernel image and the bootsector (boot.db? I forget what it's called; it's been so long). The LILO documentation will tell you exactly what files you need. It should be inusr-share-doc-lilo* somewhere. HTH,

-- Matt GThere is no Darkness in Eternity-But only Light too dim for us to see Brainbench MVP for Linux Admin mail: TRAP + SPAN don't belong ----------------------------- penguins, is Tux." --MegaHAL