The boot.ini file have been replaced with Boot Configuration Data (BCD). BCDEdit is the primary tool for editing the Boot Configuration Data of Windows starting with Vista and later versions of Windows.

bcdedit /set {GUID} datatype value

Example on how to change the description:
bcdedit /set {current} description “Window 2008 Server R2″
Example on how to create a MSDOS boot entry:

1. Create a new BCD store for MS-DOS
bcdedit /create {legacy} /d “MS-DOS”

2. Now it needs to be added to {bootmgr}
bcdedit /displayorder {legacy} /addlast

3. Add the MS-DOS partition, Windows 2008 Server will take c: as its drive letter even when it’s installed on the 2nd partition. So the MS-DOS partition is now d:
bcdedit /set {legacy} device partition=d:

4. Add the path of the bootsect.dos. Windows Server 2008 renamed it to bootsect.bak, change the extension back to .dos
bcdedit /set {legacy} path \bootsect.dos

Boot entry elements:
Identifier – Named the boot entry.
{bootmgr} = the boot manager
{current} = the OS selected to boot at startup.
{default} = the default OS selected to boot the PC.
{ntldr} = Windows Legacy OS Loader (for windows xp)
The GUID in {} is the unique codename that the system gives to each boot entry and cannot be changed.

Device – The drive or virtual image that the system will use to boot the boot entry.

Path – Location on the device where the bootloader file is found.

Description – Friendly name we give to our boot entry.