GNU GRUB 2：系统引导器的领导者

GNU GRUB 2 是相对于其前身GNU GRUB LEGACY（GNU GRUB 0.97）而言的。目前仍处于不断开发阶段，最新版本为：grub-1.97.1.tar.gz-2009-11-09

基本知识

设备名：（hdm）：m为从0开始，表示第一个硬盘

设备分区：（hdm，n）：m为从0开始，表示第一个硬盘。在grub 2 中，n从1开始，表示第一个分区，而不再是传统grub 的0。据me的分析：此举是为了统一 和命令 liunx 中对 root参数的分区表示？？！

GRUB 2和 GRUB LEGACY 的 命令区别

• kernel命令被弃用，被linux、linux16、multiboot替换
• 添加了变量的概念：之前很多的命令被设置相应的变量的方式替换，最明显的有：root、default、debug；与之配合，添加了：set、unset命令
• 添加了模块的概念：配合的命令有：insmod、rmmod、lsmod
• 添加虚拟设备支持：loopback
• 减少了网络支持功能：
• 增加了文件处理功能：ls、search
• 规范了命令、变量的命名：如color命令被两个新的变量menu_color_normal 和 menu_color_highlight 替换

Command	GRUB Legacy	GRUB 2	Comments	Group
blocklist	yes	yes
boot	yes	yes
bootp	yes	no	network support is missing
cat	yes	yes
chainloader	yes	yes	ex. of use chainloader (hd0,1)+1
cmp	yes	yes
color	yes	replaced	now two variables (menu_color_{normal,highlight})
configfile	yes	yes	default file is /grub.cfg	Menu only
debug	yes	replaced	now a variable
default	yes	yes	now a variable
device	yes	replaced	replaced with loopback
dhcp	yes	no	network support is missing
displayapm	yes	no	maybe useless
displaymem	yes	replaced	replaced by lsmmap
embed	yes	no	unnecessary
fallback	yes	replaced	now a variable	Menu only
find	yes	replaced	replaced with search
fstest	yes	no	how useful? "debug" variable should be enough
geometry	yes	no	ls should suffice
halt	yes	yes
help	yes	yes
hiddenmenu	yes	replaced	see Hiddenmenu	Menu only
hide	yes	replaced	Now a part of parttool
ifconfig	yes	no	network support is missing
impsprobe	yes	no	useless
initrd	yes	yes
insmod	no	yes	Insert a module
install	yes	no	unnecessary
ioprobe	yes	no	useless
kernel	yes	replaced	replaced with multiboot, linux, etc.
keystatus	no	yes	Check key modifier status
linux	no	yes	Load a 32-bit linux kernel
linux16	no	yes	Load a 16-bit zImage (Memtest86+)
lock	yes	replaced	Implemented differently
loopback	no	yes	Make a device from a file
ls	no	yes
lsmod	no	yes	List modules
makeactive	yes	replaced	Now a part of parttool
map	yes	replaced	replaced by drivemap
md5crypt	yes	no	should be implemented as a utility
module	yes	yes
modulenounzip	yes	no	should be merged into module
multiboot	no	yes	Load a multiboot kernel
pager	yes	replaced	now a variable
partnew	yes	no	Usefull to create/manage partitions without additional programs
parttype	yes	replaced	Now a part of parttool
password	yes	yes	Required for security
pause	yes	no	how useful?
quit	yes	no	synonym of halt or reboot?
rarp	yes	no	used?
read	yes	replaced	replaced with dump
reboot	yes	yes
rescue	no	yes	Enter rescue mode
rmmod	no	yes	Remove a module
root	yes	replaced	now a variable
rootnoverify	yes	no	useless
savedefault	yes	replaced	replace by load_env/save_env
search	no	yes	Search devices by a file or a filesystem label
serial	yes	yes
set	no	yes	Set a variable
setkey	yes	no	useful
setup	yes	no	unnecessary
terminal	yes	yes	timeout support is missing
terminfo	yes	yes	not completed yet
testload	yes	no	how useful?
testvbe	yes	replaced	replaced with videotest (there is also vbetest command for vbe specifics)
tftpserver	yes	no	network support is missing
timeout	yes	yes		Menu only
title	yes	yes	shortcut support would be nice	Menu only
unhide	yes	replaced	Now a part of parttool
unset	no	yes	Unset a variable
uppermem	yes	no	evil necessity!
vbeprobe	yes	replaced	replaced with vbeinfo