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How does linux boot

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I know the subject of this email might be pretty simple. But I've really got
confused as to how Linux (or other OS's work). I'll be specific to linux.

This is the way I understand.
The computer is on. The BIOS loads the boot-loader. The boot-loader loads the
kernel image. If the kernel image has modules, initrd also gets loaded so
that appropriate modules can be loaded for the kernel to identify the
hardware, filesystems etc etc...

Now here is what confuses me !
Say, My machine has a scsi disk in it. In normal scenarios it's obvious that
I'll be using a modular kernel with initrd support shipped by my Linux
distribution vendor. Fine till now.

OS installation is done.. The kernel image, the initrd image etc are all
stored on the disk.
Now the boot loader loads and then loads the kernel image along with the
initrd image.

So, Is the boot-loader so smart and powerful (much more that the kernel) that
it reads data from the disk without knowing the type of disk and the
filesystem type ? I mean the kernel requires modules to be loaded to detect
the type of disk (scsi or ide) , type of filesystem etc.. The boot-loader
doesn't require anything ?  Amazing.

If yes, the boot-loader is smart enough. Why not use it's master-piece code
into the kernel ? :-)

If no, What have I missed to RTFM ? Any good docs ?

- - --
Ritesh Raj Sarraf
RESEARCHUT -- http://www.researchut.com
Gnupg Key ID: 04F130BC
"Stealing logic from one person is plagiarism, stealing from many is
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