标签：linux磁盘管理
Linux磁盘管理
I/O Ports: I/O设备地址；
一切皆文件：
open(), read(), write(), close()
块设备：block，存取单位“块”，磁盘
字符设备：char，存取单位“字符”，键盘
设备文件：关联至一个设备驱动程序，进而能够跟与之对应硬件设备进行通信；
设备号码：
主设备号：major number, 标识设备类型
次设备号：minor number, 标识同一类型下的不同设备
[root@MyServer ~]# ll /dev/ total 0 drwxr-xr-x 2 root root 680 Jul 18 13:22 block drwxr-xr-x 2 root root 2420 Jul 18 13:22 char crw------- 1 root root 5, 1 Jul 18 13:22 console lrwxrwxrwx 1 root root 11 Jul 18 13:22 core -> /proc/kcore drwxr-xr-x 4 root root 80 Jul 18 13:22 cpu crw-rw---- 1 root root 10, 61 Jul 18 13:22 cpu_dma_latency crw-rw---- 1 root root 10, 62 Jul 18 13:22 crash drwxr-xr-x 5 root root 100 Jul 18 13:22 disk brw-rw---- 1 root disk 253, 0 Jul 18 13:22 dm-0 brw-rw---- 1 root disk 253, 1 Jul 18 13:22 dm-1 brw-rw---- 1 root disk 253, 2 Jul 18 13:22 dm-2 lrwxrwxrwx 1 root root 3 Jul 18 13:22 fb -> fb0 crw-rw---- 1 root root 29, 0 Jul 18 13:22 fb0 lrwxrwxrwx 1 root root 13 Jul 18 13:22 fd -> /proc/self/fd crw-rw-rw- 1 root root 1, 7 Jul 18 13:22 full crw-rw-rw- 1 root root 10, 229 Jul 18 13:22 fuse drwxr-xr-x 2 root root 40 Jul 18 13:22 hugepages crw------- 1 root root 229, 0 Jul 18 13:22 hvc0 crw-rw---- 1 root dialout 229, 1 Jul 18 13:22 hvc1 crw-rw---- 1 root dialout 229, 2 Jul 18 13:22 hvc2 crw-rw---- 1 root dialout 229, 3 Jul 18 13:22 hvc3 crw-rw---- 1 root dialout 229, 4 Jul 18 13:22 hvc4 crw-rw---- 1 root dialout 229, 5 Jul 18 13:22 hvc5 crw-rw---- 1 root dialout 229, 6 Jul 18 13:22 hvc6 crw-rw---- 1 root dialout 229, 7 Jul 18 13:22 hvc7 drwxr-xr-x 2 root root 100 Jul 18 13:22 input crw-rw---- 1 root root 1, 11 Jul 18 13:22 kmsg srw-rw-rw- 1 root root 0 Jul 18 13:22 log brw-rw---- 1 root disk 7, 0 Jul 18 13:22 loop0 brw-rw---- 1 root disk 7, 1 Jul 18 13:22 loop1 brw-rw---- 1 root disk 7, 2 Jul 18 13:22 loop2 brw-rw---- 1 root disk 7, 3 Jul 18 13:22 loop3 brw-rw---- 1 root disk 7, 4 Jul 18 13:22 loop4 brw-rw---- 1 root disk 7, 5 Jul 18 13:22 loop5 brw-rw---- 1 root disk 7, 6 Jul 18 13:22 loop6
主设备号7 次设备号5或者6
brw-rw---- 1 root disk 7, 5 Jul 18 13:22 loop5
brw-rw---- 1 root disk 7, 6 Jul 18 13:22 loop6
硬盘接口类型：
并行：
IDE：133MB/s
SCSI：640MB/s
串口：
SATA：6Gbps
SAS：6Gbps
USB：480MB/s
rpm: rotations per minute
/dev/DEV_FILE
磁盘设备的设备文件命名：
IDE: /dev/hd
SCSI, SATA, SAS, USB: /dev/sd
不同设备：a-z
/dev/sda, /dev/sdb, ...
同一设备上的不同分区：1,2, ...
/dev/sda1, /dev/sda5
机械式硬盘：
track：磁道
cylinder: 柱面
secotr: 扇区
512bytes
如何分区：
按柱面
0磁道0扇区：512bytes
MBR: Master Boot Record
446bytes: boot loader
64bytes：分区表
16bytes: 标识一个分区
2bytes: 55AA
4个主分区；
3主分区+1扩展(N个逻辑分区)
逻辑分区
问题：UEFI, GPT？
分区管理工具：fdisk, parted, sfdisk
fdisk：对于一块硬盘来讲，最多只能管理15分区；
# fdisk -l [-u] [device...]
# fdisk device
子命令：管理功能
p: print, 显示已有分区；
n: new, 创建
d: delete, 删除
w: write, 写入磁盘并退出
q: quit, 放弃更新并退出
m: 获取帮助
l: 列表所分区id
t: 调整分区id
[root@slave Desktop]# fdisk -l Disk /dev/sda: 21.5 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 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: 0x0006e340 Device Boot Start End Blocks Id System /dev/sda1 * 1 39 307200 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 39 2358 18631680 83 Linux /dev/sda3 2358 2611 2031616 82 Linux swap / Solaris
[root@slave Desktop]# fdisk /dev/sda2
WARNING: DOS-compatible mode is deprecated. It‘s strongly recommended to
switch off the mode (command ‘c‘) and change display units to
sectors (command ‘u‘).
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 4
Partition 4 is already defined. Delete it before re-adding it.
Command (m for help): n
Command action
e extended
p primary partition (1-4)
5
Invalid partition number for type `5‘
Command action
e extended
p primary partition (1-4)
3
Invalid partition number for type `3‘
Command action
e extended
p primary partition (1-4)
2
Invalid partition number for type `2‘
Command action
e extended
p primary partition (1-4)
1
Invalid partition number for type `1‘
Command action
e extended
p primary partition (1-4)
e
Partition number (1-4): 4
Partition 4 is already defined. Delete it before re-adding it.
Command (m for help): n
Command action
e extended
p primary partition (1-4)
e
Partition number (1-4): 3
First cylinder (129-2319, default 129):
Using default value 129
Last cylinder, +cylinders or +size{K,M,G} (129-2319, default 2319): +10M
[root@slave Desktop]# fdisk -ls /dev/sda2 Disk /dev/sda2: 19.1 GB, 19078840320 bytes 255 heads, 63 sectors/track, 2319 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: 0x4f138230 Device Boot Start End Blocks Id System /dev/sda2p3 129 130 16065 5 Extended /dev/sda2p4 1 128 1028128+ 83 Linux Partition table entries are not in disk order
总结
1、通过fdisk的n指令增加一个分区；
[root@slave Desktop]# fdisk /dev/sda2
WARNING: DOS-compatible mode is deprecated. It‘s strongly recommended to
switch off the mode (command ‘c‘) and change display units to
sectors (command ‘u‘).
Command (m for help): n
Command action
l logical (5 or over)
p primary partition (1-4)
2
Invalid partition number for type `2‘
Command action
l logical (5 or over)
p primary partition (1-4)
3
Invalid partition number for type `3‘
Command action
l logical (5 or over)
p primary partition (1-4)
l
First cylinder (129-130, default 129):
Using default value 129
Last cylinder, +cylinders or +size{K,M,G} (129-130, default 130): 12K
Value out of range.
Last cylinder, +cylinders or +size{K,M,G} (129-130, default 130): 122M
Value out of range.
Last cylinder, +cylinders or +size{K,M,G} (129-130, default 130): +12K
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 22: Invalid argument.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@slave Desktop]# fdisk -ls /dev/sda2
Disk /dev/sda2: 19.1 GB, 19078840320 bytes
255 heads, 63 sectors/track, 2319 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: 0x4f138230
Device Boot Start End Blocks Id System
/dev/sda2p3 129 130 16065 5 Extended
/dev/sda2p4 1 128 1028128+ 83 Linux
/dev/sda2p5 129 129 8001 83 Linux
这里模拟测试，对已经分区的硬盘再分区(在工作中没有什么意义)
2、通过fdisk的t指令指定分区类型
[root@slave Desktop]# fdisk /dev/sda2
WARNING: DOS-compatible mode is deprecated. It‘s strongly recommended to
switch off the mode (command ‘c‘) and change display units to
sectors (command ‘u‘).
Command (m for help): t
Partition number (1-5): 2
Partition 2 does not exist yet!
Command (m for help): 2p3
2: unknown command
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table
q quit without saving changes
s create a new empty Sun disklabel
t change a partition‘s system id
u change display/entry units
v verify the partition table
w write table to disk and exit
x extra functionality (experts only)
Command (m for help): t
Partition number (1-5): 5
Hex code (type L to list codes): l
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 39 Plan 9 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 3c PartitionMagic 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 40 Venix 80286 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 41 PPC PReP Boot 85 Linux extended c7 Syrinx
5 Extended 42 SFS 86 NTFS volume set da Non-FS data
6 FAT16 4d QNX4.x 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS 4e QNX4.x 2nd part 88 Linux plaintext de Dell Utility
8 AIX 4f QNX4.x 3rd part 8e Linux LVM df BootIt
9 AIX bootable 50 OnTrack DM 93 Amoeba e1 DOS access
a OS/2 Boot Manag 51 OnTrack DM6 Aux 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 52 CP/M 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 53 OnTrack DM6 Aux a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 54 OnTrackDM6 a5 FreeBSD ee GPT
f W95 Ext‘d (LBA) 55 EZ-Drive a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 56 Golden Bow a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 5c Priam Edisk a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 61 SpeedStor a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 63 GNU HURD or Sys ab Darwin boot f2 DOS secondary
16 Hidden FAT16 64 Novell Netware af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 65 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 70 DiskSecure Mult b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 75 PC/IX bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 80 Old Minix be Solaris boot ff BBT
1e Hidden W95 FAT1
Hex code (type L to list codes): b
Changed system type of partition 5 to b (W95 FAT32)
Command (m for help): p
Disk /dev/sda2: 19.1 GB, 19078840320 bytes
255 heads, 63 sectors/track, 2319 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: 0x4f138230
Device Boot Start End Blocks Id System
/dev/sda2p3 129 130 16065 5 Extended
/dev/sda2p4 1 128 1028128+ 83 Linux
/dev/sda2p5 129 129 8001 b W95 FAT32
Partition table entries are not in disk order
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 22: Invalid argument.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
WARNING: If you have created or modified any DOS 6.x
partitions, please see the fdisk manual page for additional
information.
Syncing disks.
3、
fdisk 的退出，用q或者 w；
其中 q是 不保存退出，w是保存退出；
Command (m for help): w
或
Command (m for help): q
4、通过fdisk的d指令来删除一个分区
[root@slave Desktop]# fdisk /dev/sda2
WARNING: DOS-compatible mode is deprecated. It‘s strongly recommended to
switch off the mode (command ‘c‘) and change display units to
sectors (command ‘u‘).
Command (m for help): p
Disk /dev/sda2: 19.1 GB, 19078840320 bytes
255 heads, 63 sectors/track, 2319 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: 0x4f138230
Device Boot Start End Blocks Id System
/dev/sda2p3 129 130 16065 5 Extended
/dev/sda2p4 1 128 1028128+ 83 Linux
/dev/sda2p5 129 129 8001 b W95 FAT32
Partition table entries are not in disk order
Command (m for help): d
Partition number (1-5): 5
Command (m for help):
linux分区类型
Command (m for help): l
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 39 Plan 9 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 3c PartitionMagic 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 40 Venix 80286 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 41 PPC PReP Boot 85 Linux extended c7 Syrinx
5 Extended 42 SFS 86 NTFS volume set da Non-FS data
6 FAT16 4d QNX4.x 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS 4e QNX4.x 2nd part 88 Linux plaintext de Dell Utility
8 AIX 4f QNX4.x 3rd part 8e Linux LVM df BootIt
9 AIX bootable 50 OnTrack DM 93 Amoeba e1 DOS access
a OS/2 Boot Manag 51 OnTrack DM6 Aux 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 52 CP/M 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 53 OnTrack DM6 Aux a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 54 OnTrackDM6 a5 FreeBSD ee GPT
f W95 Ext‘d (LBA) 55 EZ-Drive a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 56 Golden Bow a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 5c Priam Edisk a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 61 SpeedStor a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 63 GNU HURD or Sys ab Darwin boot f2 DOS secondary
16 Hidden FAT16 64 Novell Netware af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 65 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 70 DiskSecure Mult b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 75 PC/IX bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 80 Old Minix be Solaris boot ff BBT
1e Hidden W95 FAT1
查看内核是否已经识别新的分区：
# cat /proc/partations
[root@slave Desktop]# cat /proc/partitions major minor #blocks name 8 0 20971520 sda 8 1 307200 sda1 8 2 18631680 sda2 8 3 2031616 sda3
通知内核重新读取硬盘分区表：
partx -a /dev/DEVICE
-n M:N
kpartx -a /dev/DEVICE
-f: force
CentOS 5: 使用partprobe
partprobe [/dev/DEVICE]
本文出自 “梁小明的博客” 博客，请务必保留此出处http://7038006.blog.51cto.com/7028006/1828237
标签：linux磁盘管理
原文地址：http://7038006.blog.51cto.com/7028006/1828237
