You cannot change a partition into an extended one or vice versa Delete it first

[root@get-linux01 ~]# fdisk /dev/sdc

The number of cylinders for this disk is set to 5221.

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)

Command (m for help): p

Disk /dev/sdc: 42.9 GB, 42949672960 bytes

255 heads, 63 sectors/track, 5221 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 (1-5221, default 1): 

Using default value 1

Last cylinder or +size or +sizeM or +sizeK (1-5221, default 5221): 

Using default value 5221

Command (m for help): t

Selected partition 1

Hex code (type L to list codes): 8e

You cannot change a partition into an extended one or vice versa

Delete it first.

Command (m for help): n  

Command action

   l   logical (5 or over)

   p   primary partition (1-4)

l

First cylinder (1-5221, default 1): 

Using default value 1

Last cylinder or +size or +sizeM or +sizeK (1-5221, default 5221): 

Using default value 5221

Command (m for help): t

Partition number (1-5): 1

Hex code (type L to list codes): 8e

You cannot change a partition into an extended one or vice versa

Delete it first.

Command (m for help): p

Disk /dev/sdc: 42.9 GB, 42949672960 bytes

255 heads, 63 sectors/track, 5221 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sdc1               1        5221    41937651    5  Extended

/dev/sdc5               1        5221    41937619+  83  Linux

Command (m for help): w

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.