有点厌倦了yum软件安装的繁琐，想安装Debian，新鲜一下。
没有光盘，只能用U盘做系统盘，不满于总是按照别人的步骤安装，稍微有些问题就解决不了，决定稍微学习一下grub的使用。
废话少说，上步骤：
1、在U盘安装grub2
条件：
电脑设为从USB设备启动。
要有一个Linux系统来安装Grub.
实施步骤：
将U盘分为2个区，第一个区为vfat格式，第二个区为ext2格式，grub安装到第二个区，将第二个区作为可引导区
1、分区
- [root@localhost ~]# fdisk /dev/sdb
- Command (m for help): d
- Selected partition 1
- Command (m for help): n
- Command action
- e extended
- p primary partition (1-4)
- p
- Partition number (1-4): 1
- First cylinder (1-487, default 1):
- Using default value 1
- Last cylinder or +size or +sizeM or +sizeK (1-487, default 487): +3072M
- Command (m for help): n
- Command action
- e extended
- p primary partition (1-4)
- p
- Partition number (1-4): 2
- First cylinder (375-487, default 375):
- Using default value 375
- Last cylinder or +size or +sizeM or +sizeK (375-487, default 487):
- Using default value 487
- Command (m for help): w
- The partition table has been altered!
- Calling ioctl() to re-read partition table.
- WARNING: Re-reading the partition table failed with error 16: 设备或资源忙.
- The kernel still uses the old table.
- The new table will be used at the next reboot.
- Syncing disks.
2、格式化分区
卸载U盘：在桌面右键点击“删除文件卷”
插上U盘
- [root@localhost ~]# ls /dev/sd*
- /dev/sda /dev/sda1 /dev/sda2 /dev/sda3 /dev/sda4 /dev/sda5 /dev/sda6 /dev/sda7 /dev/sda8 /dev/sdb /dev/sdb1 /dev/sdb2
- [root@localhost ~]# umount /dev/sdb1
- [root@localhost ~]# umount /dev/sdb2
- [root@localhost ~]# mkfs.vfat /dev/sdb1
- mkfs.vfat 2.11 (12 Mar 2005)
- [root@localhost ~]# mkfs.ext2 /dev/sdb2
- mke2fs 1.39 (29-May-2006)
- Filesystem label=
- OS type: Linux
- Block size=4096 (log=2)
- Fragment size=4096 (log=2)
- 113568 inodes, 226918 blocks
- 11345 blocks (5.00%) reserved for the super user
- First data block=0
- Maximum filesystem blocks=234881024
- 7 block groups
- 32768 blocks per group, 32768 fragments per group
- 16224 inodes per group
- Superblock backups stored on blocks:
- 32768, 98304, 163840
- Writing inode tables: done
- Writing superblocks and filesystem accounting information: done
- This filesystem will be automatically checked every 24 mounts or
- 180 days, whichever comes first. Use tune2fs -c or -i to override.
3、激活/dev/sdb2
- [root@localhost ~]# fdisk /dev/sdb
- Command (m for help): a
- Partition number (1-4): 2
- Command (m for help): w
- The partition table has been altered!
- Calling ioctl() to re-read partition table.
- Syncing disks.
- [root@localhost ~]# fdisk -l
- ...
- Disk /dev/sdb: 4008 MB, 4008706048 bytes
- 255 heads, 63 sectors/track, 487 cylinders
- Units = cylinders of 16065 * 512 = 8225280 bytes
- Device Boot Start End Blocks Id System
- /dev/sdb1 1 374 3004123+ 83 Linux
- /dev/sdb2 * 375 487 907672+ 83 Linux # 可引导分区
4、安装grub到U盘
查看U盘各分区的挂载情况
- [root@localhost ~]# df
- ...
- /dev/sdb2 893388 904 847104 1% /media/disk
- /dev/sdb1 2998248 4 2998244 1% /media/disk-1
- [root@localhost ~]# grub-install --root-directory=/media/disk --no-floppy /dev/sdb2
- Probing devices to guess BIOS drives. This may take a long time.
- Installation finished. No error reported.
- This is the contents of the device map /media/disk/boot/grub/device.map.
- Check if this is correct or not. If any of the lines is incorrect,
- fix it and re-run the script `grub-install'.
- (hd0) /dev/sda
- (hd1) /dev/sdb
5、安装到U盘的MBR
- [root@localhost ~]# grub
- GNU GRUB version 0.97 (640K lower / 3072K upper memory)
- [ Minimal BASH-like line editing is supported. For the first word, TAB
- lists possible command completions. Anywhere else TAB lists the possible
- completions of a device/filename.]
- grub> root (hd1,
- Possible partitions are:
- Partition num: 0, Filesystem type unknown, partition type 0x83
- Partition num: 1, Filesystem type is ext2fs, partition type 0x83
- grub> root (hd1,1)
- Filesystem type is ext2fs, partition type 0x83
- grub> setup (hd1)
- Checking if "/boot/grub/stage1" exists... yes
- Checking if "/boot/grub/stage2" exists... yes
- Checking if "/boot/grub/e2fs_stage1_5" exists... yes
- Running "embed /boot/grub/e2fs_stage1_5 (hd1)"... 15 sectors are embedded.
- succeeded
- Running "install /boot/grub/stage1 (hd1) (hd1)1+15 p (hd1,1)/boot/grub/stage2 /boot/grub/grub.conf"... succeeded
- Done.
- grub> quit
参考网址：http://blog.csdn.net/duyiwuer2009/article/details/7799687
接下来重启，并用grub引导：
重启计算机，将会看到多了一个grub启动选项。选择它，进入grub提示符。输入如下命令：grub>kernel (hd0,0)/vmlinuz root=/dev/ram ramdisk_size=20000 devfs=mount,dall|grub>initrd (hd0,0)/initrd.gz|grub>boot|
注：在grup>提示符下，输入“|”约定表示回车注： (hd0,0)表示第一块硬盘的第一分区， (hd0,1)表示第一块硬盘的第二分区 (hd1,0)表示第二块硬盘的第一分区。依此类推，依自己实际iso所在位置不同而改变
接着马上就会进入安装界面了。
接下来处理"Incorrect CD-ROM detected"错误：
ubuntu官网这样解决的：
If you get "Incorrect CD-ROM detected" error on detection stage, reboot, press F6 and then ESC to go to manual boot line editing, and add the option 'cdrom-detect/try-usb=true'. On Ubuntu 9.10 server edition the install menu will be shown right after reboot. Chose "Help" and then press F6.
但是，我试了没用。。。囧
下面的我用了可以，推荐大家试一下：
In my case the commands below used
“/dev/sdb1” as “/dev/<usb drive partition device file>” and
“/mnt/iso/ubutnu-10.04-server-i386.iso” as “/mnt/usb/<iso file>”
but yours my vary.
When you get the screen with “Load CD-ROM driver from removable media?” press ALT-F2 to get a console and enter these commands:
mkdir /mnt/usb /mnt/iso
mount –t vfat /dev/<usb drive partition device file> /mnt/usb
mount –t iso9660 –o loop /mnt/usb/<iso file> /mnt/iso
ALT-F1 to return to installation dialog and answer as follows:
Load CD-ROM driver from removable media? <No>
Manually select CD-ROM module and device> <Yes>
Module needed for accessing the CD-ROM: none
Device file for accessing the CD-ROM: /dev/loop0
翻译一下：就是我用/dev/sdb1代表我u盘的分区
用/mnt/iso/ubun...代表我iso文件所在位置。
当通过grub进入安装菜单后，按组合键：alt+f2 进入命令窗口，输入以下：
mkdir /mnt/usb /mnt/iso
mount –t vfat /dev/<usb drive partition device file> /mnt/usb
mount –t iso9660 –o loop /mnt/usb/<iso file> /mnt/iso
可以根据自己情况修改。然后再alt+f1回去，选择如下：
Load CD-ROM driver from removable media? <No>
Manually select CD-ROM module and device> <Yes>
Module needed for accessing the CD-ROM: none
Device file for accessing the CD-ROM: /dev/loop0
over!!!!!!!!!!!!!!!!!!!!!!