Make A Bootdisk
Do you have a working Linux boot disk? If you do not you should make one now! You may need it to get into your system some day. A good boot disk has saved me allot of trouble on a few occasions.
With Linux there is usually more than one way to do a job, and making a boot disk is no different. Here I will discuss a few options.
The old tried and true method for making a boot disk was to use the "mkbootdisk" command.
First put a blank disk in the floppy drive but do not mount it, and as root enter the command fdformat /dev/fd0. This will do a low level format of the disk then it will verify the format, if the verify shows any errors trash the disk and try another. The quality of floppy disks these days is very poor, many new disks will have bad tracks or sectors right out of the box.
Find the version of the kernel you are using.
With the disk still not mounted.
Enter the following command as root,
using the correct kernel version number for your computer.
This method is somewhat out dated because on many systems today the kernel is too large to fit on a floppy disk. Also many computers don't even have floppy drives anymore. If your computer dose have a floppy drive you can use grub or lilo to make a boot floppy by simply installing the bootloader to a floppy disk instead of the hard drive.
A boot disk made this way has the advantage of booting faster because it boots the kernel from the hard drive instead of a copy on a slow floppy disk, and also allows you to pass additional parameters to the kernel by adding them to the configuration files. But if the kernel image on the hard drive becomes corrupted then this boot disk won't do you any good.
Here's how to make a grub boot floppy.
Put a blank floppy in the drive but do not mount it yet:
Now run Grub.
You now have a Grub boot floppy, test
it to be sure it works properly.
note your system may use /media/floppy
or /floppy or something else instead of /mnt/floppy.
And finally what I think is the best option (the one I use), is a bootable CD using Grub as the boot loader. With a CD you can put the kernel (or a few different kernels) on the CD and it will boot as fast as the kernel on the hard drive.
To make a Grub CD you need the file "stage2_eltorito", if Grub is on your system then you should already have every thing you need. Start by creating a directory in your home directory in which to put together the files for the CD.
Find "stage2_eltorito" with the "locate" command, different distros put it in different places. My Fedora system has it in /usr/share/grub/i386-redhat/
Copy your menu.lst and edit it for the CD, or create a new one. My Fedora system uses a file called grub.conf and menu.lst is a symlink to that file. Below is my menu.lst so you can see what it should look like.
Fedora or Redhat users
My bootCD menu.lst
Change the "root (hdx,x)" references to "root (cd)" to use the kernel and initrd from the CD instead of the hard drive. You can see that I have the option to boot the kernel from the hard drive or the kernel on the CD. I am also using the splashimage option, just put the splash.xpm.gz in /boot/grub of the CD and point splashimage to it.
Now create an ISO image with the following command:
And finally burn grub.iso too a CD and try out your new boot disk .