SCCM PXE
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Contents
SCCM - PXE - gPXE
Some notes from watching with wireshark
Booting via a USB stick with gPXE !
Emulating a normal PXE boot
...on a correctly booting subnet, with SCCM setup and a machine configured within it.
#!gpxe dhcp net0 set next-server XXX.XXX.32.60 chain smsboot\x64\wdsnbp.com
Goes through and works( this emulates a standard PXE boot)
Direct chain boot to pxeboot.com, using just next server
This bypasses wdsnbp.com checks.
#!gpxe dhcp net0 set next-server XXX.XXX.32.60 chain smsboot\x64\pxeboot.com (or pxeboot.n12)
What happens;
\smsboot\x64\pxeboot.com \smsboot\x64\bootmgr.exe \Boot\Fonts\wgl4_boot.ttf (not found) \smsboot\x64\boot.ini (not found) \Boot\BCD (not found) \Boot\Fonts\wgl4_boot.ttf (not found) = FAIL
Direct chain boot to pxeboot.com using just next server, specifying DHCP options 243 and 252
243 & 252 are options set from what wdsnbp.com discovers , they are set before pxeboot.com is requested.
#!gpxe
dhcp net0
set 243:string SMSTemp\2012.02.20.10.46.19.0003.{99FE0226-0DBD-45BF-8CF0-028422086DF8}.boot.var
set 252:string SMSTemp\2012.02.20.10.46.18.06.{99FE0226-0DBD-45BF-8CF0-028422086DF8}.boot.bcd
set next-server XXX.XXX.32.60
chain smsboot\x64\pxeboot.com
The flow with wireshark...
\smsboot\x64\pxeboot.com
\smsboot\x64\bootmgr.exe
\Boot\Fonts\wgl4_boot.ttf (not found)
\SMSTemp\2012.02.20.10.46.18.06.{99FE0226-0DBD-45BF-8CF0-028422086DF8}.boot.bcd (fail) -no blocksize set?
\SMSTemp\2012.02.20.10.46.18.06.{99FE0226-0DBD-45BF-8CF0-028422086DF8}.boot.bcd
\Boot\Fonts\wgl4_boot.ttf (not found)
\hiberfil.sys (not found)
\SMSImages\SMSPKG\UL100006\boot.UL100006.wim (fail) -no blocksize set?
\SMSBoot\boot.sdi (fail) -no blocksize set?
\SMSBoot\boot.sdi
\SMSImages\SMSPKG\UL100006\boot.UL100006.wim
\Boot\Fonts\wgl4_boot.ttf (not found)
\SMSTemp\2012.02.20.10.46.19.0003.{99FE0226-0DBD-45BF-8CF0-028422086DF8}.boot.var
TFTP server seems to not like unspecified block sizes. This works as far as the client trying to find the SMS/variables.dat file, which it tries to pull via a util SMSTFTP and fails.
