The "default" SysLinux menu, as given by Syslinux, has:
#---
LABEL local
MENU DEFAULT
MENU LABEL Boot from Harddisk
LOCALBOOT 0
Type 0x80
LOCALBOOT 0 just says "perform a normal HD boot"
The Type 0x80 says "boot to primary hard drive"
And, trying to not look like a fool and doing my googling before asking stupid questions... it seems what I want to use is chain.c32, rather than localboot, as it allows me more options. Still have to wrap my head around those, but they might give me what I want.
In BCDedit, things are a bit messed up through testing... seems running bcdboot on the mounted drive (seems I need to do this to make a vhdx from hyper-v bare-metal bootable) set itself as default. Not sure what else it did... so the following may not accurately reflect what will be. Also, this system has a second HD that I might not have to worry about on the final install clients. Having a lot of issues with Drive Numbers flipping about between local and PXE -> WinPE boots for imaging, but that's another problem separate from this one. No shortage of problems this time of year at a college.
Oh, and that /enum all shows a wee bit more stuff. Thanks for that.
Oh, and yes, BIOS for now, though there's a push for UEFI.
And, yes, I suspect (though I've not yet tested) that putting grub on the local HD would boot to grub after the PXE boot menu went to local drive. At this point, I'm hoping I can tame that chain.c32 enough to target individual boots. If I can do that, I win
David...
Windows Boot Manager
--------------------
identifier {bootmgr}
device partition=C:
description Windows Boot Manager
locale en-US
inherit {globalsettings}
default {default}
resumeobject {cd1fe16c-a5ad-11e8-8553-002324bc0d42}
displayorder {default}
{current}
toolsdisplayorder {memdiag}
timeout 30
Windows Boot Loader
-------------------
identifier {current}
device partition=C:
path \Windows\system32\winload.exe
description Windows 10
locale en-US
inherit {bootloadersettings}
recoverysequence {cd1fe16a-a5ad-11e8-8553-002324bc0d42}
recoveryenabled Yes
allowedinmemorysettings 0x15000075
osdevice partition=C:
systemroot \Windows
resumeobject {cd1fe168-a5ad-11e8-8553-002324bc0d42}
nx OptIn
bootmenupolicy Standard
Windows Boot Loader
-------------------
identifier {cd1fe16a-a5ad-11e8-8553-002324bc0d42}
device ramdisk=[C:]\Recovery\WindowsRE\Winre.wim,{cd1fe16b-a5ad-11e8-8553-002324bc0d42}
path \windows\system32\winload.exe
description Windows Recovery Environment
locale en-US
inherit {bootloadersettings}
displaymessage Recovery
displaymessageoverride Recovery
osdevice ramdisk=[C:]\Recovery\WindowsRE\Winre.wim,{cd1fe16b-a5ad-11e8-8553-002324bc0d42}
systemroot \windows
nx OptIn
bootmenupolicy Standard
winpe Yes
Windows Boot Loader
-------------------
identifier {default}
device vhd=[C:]\vhdx\W10CB.vhdx
path \Windows\system32\winload.exe
description Windows 10
locale en-US
inherit {bootloadersettings}
recoverysequence {cd1fe16e-a5ad-11e8-8553-002324bc0d42}
displaymessageoverride Recovery
recoveryenabled Yes
allowedinmemorysettings 0x15000075
osdevice vhd=[C:]\vhdx\W10CB.vhdx
systemroot \Windows
resumeobject {cd1fe16c-a5ad-11e8-8553-002324bc0d42}
nx OptIn
bootmenupolicy Standard
Windows Boot Loader
-------------------
identifier {cd1fe16e-a5ad-11e8-8553-002324bc0d42}
device ramdisk=[\windows\system32\winload.exe]\Recovery\WindowsRE\Winre.wim,{cd1fe16f-a5ad-11e8-8553-002324bc0d42}
path \windows\system32\winload.exe
description Windows Recovery Environment
locale en-us
inherit {bootloadersettings}
displaymessage Recovery
osdevice ramdisk=[\windows]\Recovery\WindowsRE\Winre.wim,{cd1fe16f-a5ad-11e8-8553-002324bc0d42}
systemroot \windows
nx OptIn
bootmenupolicy Standard
winpe Yes
Resume from Hibernate
---------------------
identifier {cd1fe168-a5ad-11e8-8553-002324bc0d42}
device partition=C:
path \Windows\system32\winresume.exe
description Windows Resume Application
locale en-US
inherit {resumeloadersettings}
recoverysequence {cd1fe16a-a5ad-11e8-8553-002324bc0d42}
recoveryenabled Yes
allowedinmemorysettings 0x15000075
filedevice partition=C:
filepath \hiberfil.sys
bootmenupolicy Standard
debugoptionenabled No
Resume from Hibernate
---------------------
identifier {cd1fe16c-a5ad-11e8-8553-002324bc0d42}
device vhd=[C:]\vhdx\W10CB.vhdx
path \Windows\system32\winresume.exe
description Windows Resume Application
locale en-US
inherit {resumeloadersettings}
recoverysequence {cd1fe16e-a5ad-11e8-8553-002324bc0d42}
recoveryenabled Yes
allowedinmemorysettings 0x15000075
filedevice vhd=[C:]\vhdx\W10CB.vhdx
filepath \hiberfil.sys
bootmenupolicy Standard
debugoptionenabled No
Windows Memory Tester
---------------------
identifier {memdiag}
device partition=C:
path \boot\memtest.exe
description Windows Memory Diagnostic
locale en-US
inherit {globalsettings}
badmemoryaccess Yes
EMS Settings
------------
identifier {emssettings}
bootems No
Debugger Settings
-----------------
identifier {dbgsettings}
debugtype Local
RAM Defects
-----------
identifier {badmemory}
Global Settings
---------------
identifier {globalsettings}
inherit {dbgsettings}
{emssettings}
{badmemory}
Boot Loader Settings
--------------------
identifier {bootloadersettings}
inherit {globalsettings}
{hypervisorsettings}
Hypervisor Settings
-------------------
identifier {hypervisorsettings}
hypervisordebugtype Serial
hypervisordebugport 1
hypervisorbaudrate 115200
Resume Loader Settings
----------------------
identifier {resumeloadersettings}
inherit {globalsettings}
Device options
--------------
identifier {cd1fe16b-a5ad-11e8-8553-002324bc0d42}
description Windows Recovery
ramdisksdidevice partition=C:
ramdisksdipath \Recovery\WindowsRE\boot.sdi
Device options
--------------
identifier {cd1fe16f-a5ad-11e8-8553-002324bc0d42}
description Windows Recovery
ramdisksdidevice vhd=[C:]\vhdx\W10CB.vhdx
ramdisksdipath \Recovery\WindowsRE\boot.sdi