#fdisk /dev/sda

The number of cylinders for this disk is set to 60801.
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/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x24d1ed11
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1        2432    19535008+  83  Linux
/dev/sda2            2433        3040     4883760   82  Linux swap / Solaris
/dev/sda3            3041       27355   195310237+  83  Linux
Command (m for help): d sda3
Partition number (1-4): 3
Command (m for help): p
Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x24d1ed11
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1        2432    19535008+  83  Linux
/dev/sda2            2433        3040     4883760   82  Linux swap / Solaris
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
   p   primary partition (1-4)
e
Partition number (1-4): 3
First cylinder (3041-60801, default 3041):
Using default value 3041
Last cylinder, +cylinders or +size{K,M,G} (3041-60801, default 60801): +25000M
Command (m for help): p
Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x24d1ed11
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1        2432    19535008+  83  Linux
/dev/sda2            2433        3040     4883760   82  Linux swap / Solaris
/dev/sda3            3041        6228    25607610    5  Extended
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: Устройство или ресурс занято.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.