1:放入linux的第一张安装盘
2：在boot后面输入：linux sercue（也就是安装模式）
3：进入安全模式后
引用:chroot /mnt/sysimage
vi /boot/grub/device.map
(fd0) /dev/fd0
(hd0) /dev/sda
(hd1) /dev/sdb
4. vi grub.conf
引用:# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=LABEL=/
# initrd /initrd-version.img
#boot=/dev/hda1
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
#Boot from /boot partition, /dev/hda1
title Red Hat Enterprise Linux Disk A (version)
root (hd0,0)
kernel /vmlinuz-version ro root=LABEL=/
initrd /initrd-version.img
#Boot from /boot partition, /dev/hdc1
title Red Hat Enterprise Linux Disk C (version)
root (hd1,0) 注意这里的hd1是1
kernel /vmlinuz-version ro root=LABEL=/
initrd /initrd-version.img
5：/sbin/grub
6： grub> root (hd1,0)
grub> setup (hd1)
7：grub> root (hd0,0)
grub> setup (hd0)
8：quit
10：reboot
11：将bios的boot启动顺序给为
1：Cdrom
2：hd0
3：hd1