Linux磁盘管理命令（fdisk，mount，umount，mkfs）
查看磁盘：fdisk -l
[root@wendyhost ~]# fdisk -l
Disk /dev/sda: 64.4 GB, 64424509440 bytes
255 heads, 63 sectors/track, 7832 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 1057 8385930 83 Linux
/dev/sda3 1058 1815 6088635 82 Linux swap / Solaris
/dev/sda4 1816 7832 48331552+ 5 Extended
/dev/sda5 1816 2859 8385898+ 83 Linux
/dev/sda6 2860 3381 4192933+ 83 Linux
/dev/sda7 3382 3903 4192933+ 83 Linux
/dev/sda8 3904 7832 31559661 83 Linux
Disk /dev/sdb: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk /dev/sdb doesn't contain a valid partition table
以上有2块磁盘，/dev/sdb没有分区
进行分区： fdisk /dev/sdb
[root@wendyhost ~]# fdisk /dev/sdb
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help):m 帮助
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): p查看分区
Disk /dev/sdb: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
Command (m for help): n加分区add a new partition
Command (m for help): n
Command action
e extended 扩展分区可以添加一个
p primary partition (1-4)主分区，只能添加一个到4个
- 主分区+扩展分区不能超过4个
- 扩展分区是不能用的，只能在扩展分区下添加逻辑分区
- 一块磁盘可以分14个分区
e
Partition number (1-4): 1
First cylinder (1-130, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-130, default 130):
Using default value 130
Command (m for help): p
Disk /dev/sdb: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sdb1 1 130 1044193+ 5 Extended
Command (m for help): n
Command action
l logical (5 or over)
p primary partition (1-4)
l
First cylinder (1-130, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-130, default 130): +50M
Command (m for help): p
Disk /dev/sdb: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sdb1 1 130 1044193+ 5 Extended
/dev/sdb5 1 7 56164+ 83 Linux
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: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
[root@wendyhost ~]#
[root@wendyhost ~]# partprobe
Warning: Unable to open /dev/sr0 read-write (Read-only file system). /dev/sr0 has been opened read-only.
[root@wendyhost ~]#
使用分区：mkfs.ext3 /dev/sdb5
[root@wendyhost ~]# mkfs.ext3 /dev/sdb5
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
14056 inodes, 56164 blocks
2808 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=57671680
7 block groups
8192 blocks per group, 8192 fragments per group
2008 inodes per group
Superblock backups stored on blocks:
8193, 24577, 40961
Writing inode tables: done
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 20 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
将分区mount到目录上，这样才能使用
[root@wendyhost ~]# mount
/dev/sda2 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/sda8 on /u01 type ext3 (rw)
/dev/sda7 on /home type ext3 (rw)
/dev/sda6 on /var type ext3 (rw)
/dev/sda5 on /usr type ext3 (rw)
/dev/sda1 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
.host:/ on /mnt/hgfs type vmhgfs (rw,ttl=1)
none on /proc/fs/vmblock/mountPoint type vmblock (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
以上是开机自动mount的
将sdb5分区mount到目录/mnt上：mount /dev/sdb5 /mnt
[root@wendyhost ~]# mount /dev/sdb5 /mnt
[root@wendyhost ~]# cd /mnt
[root@wendyhost mnt]# pwd
/mnt
[root@wendyhost mnt]# ls
lost+found
[root@wendyhost mnt]# touch test
[root@wendyhost mnt]# ls
lost+found test
创建了test文件，该文件是写在sdb5分区的磁盘上。
[root@wendyhost mnt]# mount
/dev/sda2 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/sda8 on /u01 type ext3 (rw)
/dev/sda7 on /home type ext3 (rw)
/dev/sda6 on /var type ext3 (rw)
/dev/sda5 on /usr type ext3 (rw)
/dev/sda1 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
.host:/ on /mnt/hgfs type vmhgfs (rw,ttl=1)
none on /proc/fs/vmblock/mountPoint type vmblock (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
/dev/sdb5 on /mnt type ext3 (rw)
如果umount /dev/sdb5，则在/mnt下看不到test文件。
[root@wendyhost /]# umount /dev/sdb5
