[root@oracle ~]# fdisk -l

Disk /dev/sdb: 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: 0x00000000

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: 0x0006b59c

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@oracle ~]# fdisk /dev/sdb 

Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel

Building a new DOS disklabel with disk identifier 0x09f38795.

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)

 

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): m

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): n

Command action

  e  extended                                  ···扩展分区

  p  primary partition (1-4)                          ···主分区

p

Partition number (1-4): 1

First cylinder (1-2610, default 1): 

Using default value 1

Last cylinder, +cylinders or +size{K,M,G} (1-2610, default 2610): 

Using default value 2610 

Command (m for help): p

 

Disk /dev/sdb: 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: 0x09f38795

 

  Device Boot   Start     End   Blocks  Id System

/dev/sdb1        1    2610  20964793+ 83 Linux

 

Command (m for help): w

The partition table has been altered!

 

Calling ioctl() to re-read partition table.

Syncing disks. 

[root@oracle ~]# mkfs.ext4 /dev/sdb

mkfs.ext4: invalid fragment size - /dev/sdb 

[root@oracle ~]# mount /dev/sdb /oracle/

You have new mail in /var/spool/mail/root

[root@oracle ~]# df -TH

Filesystem   Type  Size Used Avail Use% Mounted on

/dev/sda2   ext4  19G  11G 7.3G 60% /

tmpfs     tmpfs 2.1G  74k 2.1G  1% /dev/shm

/dev/sda1   ext4  297M  29M 253M 11% /boot

/dev/sdb    ext4  22G  47M  20G  1% /oracle 

/dev/sdb    /oracle     ext4  defaults,noatime    0 0