编译好内核后改grub.conf的问题

yanlv

编译完内核后
cp arch/i386/boot/bzImage /boot/vmlinuz-mykernel
原来的grub.conf
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You do not have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /, eg.
#          root (hd0,0)
#          kernel /boot/vmlinuz-version ro root=/dev/hda1
#          initrd /boot/initrd-version.img
#boot=/dev/hda
default=0
timeout=10
splashimage=(hd0,0)/boot/grub/splash.xpm.gz
title Red Hat Linux (2.4.20- A.ZA.A.ZA.Fighting
        root (hd0,0)
        kernel /boot/vmlinuz-2.4.20-8 ro root=LABEL=/
        initrd /boot/initrd-2.4.20-8.img
title Microsoft Windows XP Good Weather
        map (hd0) (hd1)
        map (hd1) (hd0)
        rootnoverify (hd1,0)
        makeactive
        chainloader +1
        boot
append="hdd=ide-scsi"
是不是只要把kernel /boot/vmlinuz-2.4.20-8 改为/boot/vmlinuz-mykernel就行了，
可是不懂initrd这个语句是干什么的，怎么改