[syslinux] [RFC, PATCH] core/pxe: Add architecture-specific discovery request for PXE config file

[Gene Cumm]

On Mon, Feb 24, 2014 at 11:56 PM, Don Cupp <doncuppjr at yahoo.com> wrote:
> https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Installation_Guide/s1-netboot-pxe-config-efi.html

Don, thanks for the reference.  If Jeremy is doing this, then the
dhcpd DOES INFACT know EXACTLY what it's booting and can easily use
different directories.

Without something like the macroing that HPA pointed out (not
implemented), you're stuck needing the COM32 modules in different
directories which requires that a config specifies a different path.
I'd still say that completely different paths for the base binary,
ldlinux and config is the best differentiation strategy followed by a
content reuse strategy.  Between symlinks on the tftpd host and
Syslinux's INCLUDE/CONFIG directives, you can get a pretty manageable
system.

-- 
-Gene

> On Monday, February 24, 2014 8:50 PM, Gene Cumm <gene.cumm at gmail.com> wrote:
>
> On Mon, Feb 24, 2014 at 10:09 PM, Jeremy Kerr <jk at ozlabs.org> wrote:
>> Hi Gene,
>>
>>>> What I'm looking to do here is establish a bit of a convention for
>>>> allowing machines of multiple architectures to be perform PXE
>>>> configuration in a uniform way (in this case, without requiring the DHCP
>>>> server to send out different lease parameters in response to the
>>>> client's DHCP architecture ID).
>>>
>>> How do you have multiple architectures booting from the same directory
>>> at this time?  What exact string is used by network boot clients of
>>> each of the three architectures?
>>
>> This is only in-development at this stage, so I only have this going in
>> a virtual environment. I have machines of separate architectures (x86
>> PC-BIOS and PowerPC OPAL) booting from the same directory of pxe
>> configuration files:
>>
>>  /pxelinux.cfg/arch-0000
>>  /pxelinux.cfg/arch-000e
>>
>> The arch-0000 file is being used by for the x86 machines running
>> pxelinux, and arch-000e for the powerpc machines running petitboot.
>
> No, what string is used for a file name in the TFTP request for the
> boot binaries (ie pxelinux.0 bootia32.efi bootx64.efi)?  How do you
> manipulate the DHCP offer to evoke this behavior (ie a BIOS machine
> receiving "pxelinux.0" in the DHCP/BOOTP field "file")
>
> http://tools.ietf.org/html/rfc2131 Figure 1 for field file.