The following steps describe the overall process for booting into a boot image from the network

The following steps describe the overall process for booting into a boot image from the network:

1. The BIOS or Extensible Firmware Interface (EFI) of the computer signals a request to boot from the network.

2. PXE ROM gets an IP address from a Dynamic Host Control Protocol (DHCP) server and locates a server.

3. PXE ROM downloads a network boot program (NBP) by using Trivial File Transfer Protocol (TFTP). For EFI, skip to step 5.

4. The NBP downloads the operating system loader by using TFTP, using the User Data Protocol (UDP) stack from the PXE ROM.

5. The loader downloads (using TFTP) the associated files needed to boot into Windows PE from RAMDISK. These files include the following:

a. A Boot Configuration Data (BCD) store. This replaces the Boot.ini file, which tells the loader how to boot the operating system.

b. An .sdi disk image.

c. The boot image, in .wim format.

d. Font files for the boot menu. You can configure the boot menu to be in a different language, so these files are downloaded to display the localized boot menu.
The TFTP download occurs using the UDP stack from the PXE ROM. The TFTP protocol is implemented in the loader, so the user can see a progress bar.

6. The RAMDISK is produced by creating the disk image in memory and appending the .wim file to the disk.

7. Windows PE boots by using the image in the .wim file.
The following diagram illustrates what happens in the RAM of a client computer.


To enable PXE Booting in your environment the Distribution Server will have to be a PXE booting point, the Boot Images will have to be distributed to it and DHCP options will have to be changed.

Can you please set the following options on your DHCP Server
066 Boot Server Hostname – MyServerName.MyDomain.COM
067 Bootfile Name - \SMSBoot\x86\wdsnbp.com

This applies to all Distribution points if you require PXE imaging.