[syslinux] Problems with booting ReactOS over network using pxelinux

[Smith John]

Hello syslinux mailing list users,

I've initially filed a bug about my problem [1], but people from irc channel suggested to ask for help here. 

I have a PXE server based on syslinux 4.05 that distributes ReactOS to client machines over network.
It has a pretty simple pxelinux.cfg/default, with the following contents (that were suggested by ReactOS wiki [2]):

	DEFAULT chain.c32
	APPEND file=freeldr.sys seg=0x0F80 keeppxe

I try to make my PXE server distribute multiple distros, which requires a boot menu, so [3] I've decided to get a more recent release of syslinux.
I've updated to 6.03 and my current config stopped working. I've tried different configs like

1. [4]
	DEFAULT chain.c32 file=freeldr.sys seg=0x0F80 keeppxe

2. [5]
	DEFAULT chain.c32 reactos=freeldr.sys save

3. [6]
	DEFAULT reactos
	LABEL reactos
	COM32 chain.c32
	APPEND reactos=freeldr.sys

4. [6]
	DEFAULT reactos
	LABEL reactos
	COM32 chain.c32
	APPEND reactos=freeldr.sys keeppxe

All of the above configs lead to the same error:

	ERR: When syslinux is not booted from physical disk (or its emulation), 'boot' and 'fs' are meaningless.
	boot: _

I know I could stick with syslinux 4.05, but I don't know yet what other OSes I'll want my PXE server to distribute, so I'd like to make it work with syslinux 6.03.


[1] - http://bugzilla.syslinux.org/show_bug.cgi?id=61
[2] - https://www.reactos.org/wiki/Building_PXE-ready_ReactOS#Creating_contents_on_TFTP_server
[3] - turns out, 4.05 supports menu.c32 too, so updating is actually unnecessary.
[4] - http://www.syslinux.org/wiki/index.php/Directives/append#default this wiki page says since v.5 syslinux uses a one line config where old versions used DEFAULT + APPEND.
[5] - although reactos wiki suggests to use a 'file=freeldr.sys seg=0x0F80' approach, syslinux wiki page http://www.syslinux.org/wiki/index.php/Comboot/chain.c32 suggests to use 'reactos=freeldr' approach (although it uses a different 'seg' value).
[6] - an irc channel member suggested to 'always use labels'.
[7] - the same member later suggested it might have something to do with 'keeppxe'.