在Linux扩展LVM时，使用fdisk创建分区时，在磁盘上新建扩展分区（逻辑分区），修改分区格式，指定分区类型为8e时，报错“You cannot change a partition into an extended one or vice versa Delete it first.”。 具体操作如下所示：
[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.
其实出现这个错误，是因为分区号（Partition number）号弄错了（因为必须保留1-4这4个数字给主分区和扩展分区使用，所以逻辑分区的数字必须从5开始）。赤裸裸的要被鄙视啊！ 按照下面操作即可解决问题。
