Without rebooting the machine, how can one know about the bootloader installed ?? and lilo.conf and grub.conf are both present..(supposing i have both istalled grub and lilo at different times)..plz F1..

Without rebooting? Try this (as root):

(Obviously replace hda with the appropriate drive, if necessary.)

If you get some output, you have grub installed, if you get no output, it's LILO.

Sidenote: You must grep for GRUB, don't try LILO, because if you installed lilo, then installed grub, the mbr will still have "LILO" in the "filesystem descriptor string" (it's not called that, but I can't remember the correct name off-hand) as grub doesn't change that.

i have done that..i have installed grub as my bootloader.. so when i read the contents of mbr i find GRUB in the output..but i hane never installed lilo ( even when i try to install lilo, i get lot of dependency issues-thats a long list)

when i try to read the mbr, please tell me about the output of these three conditions :
1. u have installed lilo only and no other bootloader.
2. first u have installed grub then u install lilo.
3. u've lilo at first, then u install grub..

plz reply..

I'm not sure how this will help you....someone would have to do all those combinations and then dump the mbr contents---very tedious task which I'd be willing to bet has not ever been done and documented.

What is your end goal?
Do you have a working system and you need to change something?

see mr. always a thing is not done for benefit ..this is just an interest.. just a query came in my mind and i posted. and i dont work anywhere, im just a fresher anyways thanx..

The mbr has 5 parts (this applies to x86 DOS mbr).

1. a short jump to the start of the boot loader
2. a bunch of drive parameters--number of heads/tracks etc (google for the details).
3. boot loader code
4. partition table.
5. the last two bytes are 0x55AA to indicate a valid boot loader.

Obviously grub and lilo have their own boot code, which will overwrite whatever was there before. The other parts aren't changed by grub or lilo, since that isn't their business. That's really the only difference, except as I mentioned before, there is an 8 byte text field (space padded) to describe the OS/filesystem (which might contain something like "FAT32" or whatever), which lilo writes to, but grub doesn't bother, so it will contain whatever was there before you installed grub.