How to format the Linux Hard disk

[root@muthu ~]# fdisk -l

Disk /dev/sda: 107.3 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 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        1288    10241437+  83  Linux
/dev/sda3            1289        1549     2096482+  82  Linux swap
/dev/sda4            1550       13054    92413912+   5  Extended
/dev/sda5            1550       13054    92413881   83  Linux

Disk /dev/sdb: 75.1 GB, 75161927680 bytes
255 heads, 63 sectors/track, 9137 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table
[root@muthu /]# 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.


The number of cylinders for this disk is set to 9137.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

Command (m for help): p

Disk /dev/sdb: 75.1 GB, 75161927680 bytes
255 heads, 63 sectors/track, 9137 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
e
Partition number (1-4): 1
First cylinder (1-9137, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-9137, default 9137):
Using default value 9137

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

Calling ioctl() to re-read partition table.
Syncing disks.
[root@muthu /]# mkfs -t ext3 /dev/sdb
mke2fs 1.35 (28-Feb-2004)
/dev/sdb is entire device, not just one partition!
Proceed anyway? (y,n) y
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
9175040 inodes, 18350080 blocks
917504 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
560 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
        4096000, 7962624, 11239424

Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information:
done

This filesystem will be automatically checked every 36 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.
[root@muthu /]# mount /dev/sdb /backup/
[root@muthu /]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2             9.7G  7.6G  1.7G  83% /
/dev/sda1              99M   20M   74M  22% /boot
none                  501M     0  501M   0% /dev/shm
/dev/sda5              87G   88M   83G   1% /oracle
/dev/hdc              2.6G  2.6G     0 100% /media/cdrom
/dev/sdb               69G   84M   66G   1% /backup
[root@muthu /]#