Making grub boot the CD-ROM
Step 1: Download the memdisk.bin from here or if you have syslinux installation, you can use the installed memdisk.bin.
Step 2: Download the sbootmgr.dsk from here or if you have any version of Slackware CD-1, /isolinux/sbootmgr/sbootmgr.dsk file you can use.
Step 3: Copy both memdisk.bin and sbootmgr.dsk in your grub existing grub installation path, /boot/grub.
Step 4: Add the following entry in your existing grub menu. Note: root(hd0,0) should be according to your configuration.
title CDROM
root(hd0,0)
kernel /boot/grub/memdisk.bin
initrd /boot/grub/sbootmgr.dsk
Step 5: I hope you need not to run grub-install again. If necessary you can do.
Step 6: Reboot the machine.
Step 7: You can see an entry called CDROM in grub menu list. Select the entry. You will be shown boot device selection screen showing all your harddisk and CDROM drives. Insert your bootable CDROM in the CD Drive and select that drive from menu. Waavv..!! your machine is booted from that CD.
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