PXE Boot files in Remote-install folder explained

PXE Boot files in Remote-install folder explained

When installing WDS for PXE Boot functionality a RemoteInstall folder will be created. Most of times I install this role on the SCCM/ConfigMgr server with MDT integration. It's also possible to use a different server for that, as long the ConfigMgr PXE service point is installed on that server also.I am explaining here for the PXE Boot files which are installed.

After installation, the following files and folders are available in the RemoteInstall folder:

SMSBoot
- abortpxe.com > Used when no advertisement is available
- bootmgfw.efi > (available in x64 folder only)
- bootmgr.exe > In Boot order this is file 3 needed
- pxeboot.com > In Boot order this is file 2 needed
- pxeboot.n12 > Can be used to skip the second F12 requirement (!)
- wdsnbp.com > In Boot order this is file 1 needed (!)
SMSIMAGES
- Boot.xxx00001.wim (WDS x86 boot image)
- Boot.xxx00002.wim (WDS x64 boot image)
SMSTemp
- A temporary folder for updating boot images
Stores
- This is the Drivers (Metadate) store

The following outlines the download process.

1. A client is directed (by using DHCP Options or the PXE Server response) to download Wdsnbp.com
2. Wdsnbp.com validates the DHCP/PXE response packet and proceeds to download PXEBoot.com.
Note: PXEBoot.com requires the client to press the F12 key to initiate PXE boot. One can rename one of the other PXE boot files (such as pxeboot.n12) to download Wdsnbp.com to a different file. 
3. PXEBoot.com downloads Bootmgr.exe and the BCD store. The BCD store must reside in a \Boot directory in the TFTP root folder. Additionally, the BCD store must be called BCD.
4. Bootmgr.exe reads the BCD operating system entries and downloads Boot.sdi and the Windows PE image (Winpe.wim).
5. Bootmgr.exe begins booting Windows PE by calling into Winload.exe within the Windows PE image.

And some additional information also:

When using DHCP Options for PXE Boot, Option 66 and 67 are needed. Option 66 must be the IP-address of your WDS server, Option 67 must be SMSBoot\x86\wdsnbp.com (which is the first file needed during the PXE Boot process).

The default pxeboot.com triggers an F12 requirement. The first F12 requirement is needed when Network Service boot is not on top of list in the BIOS boot order. The second F12 requirement is needed because of pxeboot.com, which is only needed when using Lite Touch Installation (LTI).

The second F12 requirement can be skipped however when renaming the default pxeboot.com to pxeboot.f12 and pxeboot.n12 (which means no F12) to pxeboot.com. After that the second F12 requirement is not needed anymore, also not for Lite Touch Installation (LTI). This must be done in both the x86 and x64 folder to make it functional.

Troubleshooting PXE related issue - 
Microsoft Technet