概覽：
設備文件的創建?
??????? 權限??? 設備名 類型? 主設備號 次設備號????
mknod [-m MODE] NAME type [MAJOR MINOR] 創建時，先查看是否存在設備號的沖突
零磁道零扇區是MBR：Master Boot Record
??????????? 主引導記錄
??????????? 512Bytes: 引導啟動OS
??????????????? 前446bytes: 存放程序，bootloader
??????????????? 64bytes: 分區表，每16bytes標記一個分區，一共4個分區（主分區）
??????????????? 2bytes: 55AA, MBR有效性標記?? 標記當前mbr是否有效
fdisk是不支持GPT格式的硬盤分區，parted是可以支持的???????????????
parted [options] [device [command [options...]...]]? 直接跟設備不跟其他會分區
-l, --list? 會列出所有分區信息
??? lists partition layout on all block devices
command???
mklabel label-type
???? Create a new disklabel (partition table) of label-type.? label-type should? be? one? of
???? "bsd", "dvh", "gpt", "loop", "mac", "msdos", "pc98", or "sun".

mkpart part-type [fs-type] start end
???? Make? a? part-type partition with filesystem fs-type (if specified), beginning at start
???? and ending at end (by default in megabytes).? fs-type can be one of? "fat16",? "fat32",
???? "ext2",? "HFS", "linux-swap", "NTFS", "reiserfs", or "ufs".? part-type should be one of
???? "primary", "logical", or "extended".
move partition start end
???? Move? partition? so? that it begins at start and ends at end.? Note: move never changes
???? the minor number.
rm partition
???? Delete partition.
print? Display the partition table.????
# parted /dev/sdb mkpart primary ext4 1 10G????
#parted /dev/sdb rm 1
# parted /dev/sdb print?????????????????????????
磁盤管理：

??? I/O設備：
??????? 磁盤
??????? 網卡

??? 文件：read, write, open, close

??? 設備文件：特殊文件
??????? 只有inode，而沒有數據

??????? 關聯至一個驅動程序，進而跟對應的硬件設備打交道；

??????? /dev: b, c

??????????? 每個設備都有其設備號：
??????????????? 主設備號：用于標記設備類型
??????????????? 次設備號：用于標記同一類型中的不同設備

???? mknod - make block or character special files
???? -m, --mode=MODE
????????????? set file permission bits to MODE, not a=rw - umask
??????? mknod [OPTION]... NAME TYPE [MAJOR MINOR]? 主設備號可以相同，次設備號不能相同
??????? TYPE may be:

?????? b????? create a block (buffered) special file 有緩存

?????? c, u?? create a character (unbuffered) special file 無緩存的

?????? p????? create a FIFO
??????????? 設備文件的命名：由ICANN：互聯網名稱與數字地址分配機構（Internet
???????????? Corporation for Assigned Names and Numbers）
[root@linux_basic tmp]#mknod -m 664 blocktest b 1 20
[root@linux_basic tmp]#ls -l
total 0
brw-rw-r--. 1 root root 1, 20 Jan? 4 07:38 blocktest
[root@linux_basic tmp]#rm blocktest
rm: remove block special file `blocktest'? y
[root@localhost tmp]# mknod test c 1 30
[root@localhost tmp]# ls -l
total 0
lrwxrwxrwx. 1 root root???? 8 Dec? 2 13:10 file1 -> softfile
-rw-r--r--. 1 root root???? 0 Dec? 2 13:09 softfile
crw-r--r--. 1 root root 1, 30 Dec? 2 13:27 test

??? 磁盤設備文件命名：
??????? /dev/hd:
??????????? IDE: 并口接口, 133MB/s
??????? /dev/sd:
??????????? USB: 串行
??????????? SATA: 串行接口，6Gbps/8
??????????? SCSI: 并行，(Small Computer System Interface) 小型計算機系統接口
??????????? SAS：串行，

??????????? rpm：轉數

??????? /dev/sd[a-z]
??????????? 分區：數字
??????????????? /dev/sda1
??????????????? /dev/sda2

??????????????? 分區編號：
??????????????????? 主+擴展分區：1-4
??????????????????? 邏輯分區：5開始

??? 硬盤分區：
??????? 磁道：track
??????????? 扇區：sector

??????? 柱面：cylinder：
??????????? 分區根據柱面劃分，在同一盤片上的兩面磁頭同時讀取，速度快

??????? 零磁道零扇區是MBR：Master Boot Record
??????????? 主引導記錄
??????????? 512Bytes: 引導啟動OS
??????????????? 前446bytes: 存放程序，bootloader
??????????????? 64bytes: 分區表，每16bytes標記一個分區，一共4個分區（主分區）
??????????????? 2bytes: 55AA, MBR有效性標記?? 標記當前mbr是否有效

??????????? 1T: 3主+1擴展（切割1個或多個邏輯分區）
???????????
??????? [root@linux_basic tmp]#fdisk -l | grep -A 3 "^Disk /dev/.*"
??????? Disk /dev/sda: 48.3 GB, 48318382080 bytes
??????? 255 heads（磁頭數）, 63 sectors/track每磁道多少扇區, 5874 cylinders（柱面）
??????? Units = cylinders of 16065 * 512 = 8225280 bytes
??????? Sector size (logical/physical): 512 bytes / 512 bytes
??????? --
??????? Disk /dev/mapper/vg_lvm-lv1: 12.9 GB, 12884901888 bytes
??????? 255 heads, 63 sectors/track, 1566 cylinders
??????? Units = cylinders of 16065 * 512 = 8225280 bytes
??????? Sector size (logical/physical): 512 bytes / 512 bytes
??????? --
??????? Disk /dev/mapper/vg_lvm-lv2: 10.7 GB, 10737418240 bytes
??????? 255 heads, 63 sectors/track, 1305 cylinders
??????? Units = cylinders of 16065 * 512 = 8225280 bytes
??????? Sector size (logical/physical): 512 bytes / 512 bytes???

??????? /proc:
??????? [root@linux_basic tmp]#cat /proc/partitions
??????? major minor? #blocks? name
???????
?????????? 8??????? 0?? 47185920 sda
?????????? 8??????? 1???? 204800 sda1
?????????? 8??????? 2?? 10485760 sda2
?????????? 8??????? 3?? 36494336 sda3
???????? 253??????? 0?? 12582912 dm-0
???????? 253??????? 1?? 10485760 dm-1

??? 分區創建：
???? fdisk - Partition table manipulator for Linux
???? 操作Linux分區表
??????? 查看：fdisk -l [DEVICE]...
?? fdisk工具最多可以識別15個分區
??????? 創建分區：fdisk [DEVICE]
??????????? 交互式界面，有許多子命令
??????????????? p: 顯示磁盤分區表
???????????????? p?? print the partition table
??????????????? n: new，新建分區
???????????????? n?? add a new partition
??????????????? d: delete，刪除分區
??????????????? d?? delete a partition
??????????????? t: 修改分區的系統ID
??????????????? t?? change a partition's system id
??????????????? l: 列表出所有已知的系統ID
??????????????? l?? list known partition types
?????????????????? 83? Linux
?????????????????? 82? Linux swap / So
?????????????????? 8e? Linux LVM?
?????????????????? fd? Linux raid auto
??????????????? w: 保存并退出
??????????????? w?? write table to disk and exit
??????????????? q: 不保存退出
??????????????? q?? quit without saving changes
選n后出現???????????????
???? e?? extended
?? p?? primary partition (1-4)

??????????? 對于已經有分區處于使用狀態的磁盤來講，新建分區后需要讓內核重讀其分區表：
??????????????? CentOS 5:
??????????????????? # partprobe [DEVICE]
??????????????? CentOS 6:
??????????????????? partx -a [DEVICE]
??????????????????? partx - telling the kernel about presence and numbering of on-disk partitions.
??????????????????? -a???? add specified partitions or read disk and add all partitions
??????????????????? 讀磁盤新增的分區
??????????????????? kpartx -af? [DEVICE]
??????????????????? kpartx - Create device maps from partition tables
??????????????????? -a???? Add partition mappings
??????????????????? -l???? List partition mappings that would be added -a
??????????????????? -f???? force creation of mappings; overrides ’no_partitions’ feature
????? 查看/proc/partitions,有顯示則創建成功
??????????? 分區創建工具：sfdisk和parted
------------------------------------------------------------------
Command (m for help): n
Command action
?? e?? extended
?? p?? primary partition (1-4)
e
Partition number (1-4): 1
First cylinder (1-6527, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-6527, default 6527): +5G
??????????????????????????? 注意這里設定大小時的格式
Command (m for help): p

Disk /dev/sdb: 53.7 GB, 53687091200 bytes
255 heads, 63 sectors/track, 6527 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

?? Device Boot????? Start???????? End????? Blocks?? Id? System
/dev/sdb1?????????????? 1???????? 654???? 5253223+?? 5? Extended

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
[root@lvm ~]# partx -a /dev/sdb
? Warning: Disk has a valid GPT signature but invalid PMBR.
? Assuming this disk is *not* a GPT disk anymore.
? Use gpt kernel option to override.? Use GNU Parted to correct disk.
BLKPG: Device or resource busy
error adding partition 1
[root@lvm ~]# kpartx -af /dev/sdb
? Warning: Disk has a valid GPT signature but invalid PMBR.
? Assuming this disk is *not* a GPT disk anymore.
? Use gpt kernel option to override.? Use GNU Parted to correct disk.
[root@lvm ~]# cat /proc/partitions
major minor? #blocks? name

?? 8??????? 0?? 52428800 sda
?? 8??????? 1???? 204800 sda1
?? 8??????? 2?? 10485760 sda2
?? 8?????? 16?? 52428800 sdb
?? 8?????? 17????????? 1 sdb1? 說明創建成功了
-------------------------------------------------------------------------------??
死循環的一個簡單腳本
[root@lvm ~]# bash -n hello.sh
[root@lvm ~]# ./hello.sh
Hello:ld
Again? hello:jhfld
Again? hello:n
[root@lvm ~]# cat hello.sh
#!/bin/bash
#
read -p "Hello:" kir
while true;do
if [ "$kir" == 'n' ];then
??? break;
else
??? read -p "Again? hello:" kir
fi
done
------------------------------------------------------------------
??? 練習：寫一個腳本
??????? 1、提示輸入一個對其執行分區的新硬件設備文件；
??????? 2、提醒用戶接下來的操作銷毀所有的數據，你繼續嗎？
??????????? y或yes: 繼續
??????????? n或no：退出
??????????? 其它字符：提醒輸錯了，再來一次；
??????? 3、對磁盤新建分區：
??????????? 主分區1：大小512M，
??????????? 主分區2：大小2G
??????? 4、創建完成后顯示創建的結果；
成功完成及修改次數
----------------------------------------------------------------

[root@lvm shells]# cat disk_part.sh
#!/bin/bash
#
read -p "Input a partition disk device path:" disk
read -p "The following operation will damage the all data on the disk.yes|no(y|n)?" flag

while true;do
?
? if [ "$flag" == 'n' -o "$flag" == 'no' ];then
???? break;
? elif [ "$flag" == 'y' -o "$flag" == 'yes' ];then
echo "n
p
1

+512M
n
p
2

+2G
w"|fdisk $disk > /dev/null
? partx -a $disk
? kpartx -af $disk
? fdisk -l | grep? "$disk"
? read -p "The following operation will damage the all data on the disk.yes|no(y|s)?" flag
? else
???? echo "Input error."
???? read -p "Again input:" flag
?? fi
done