Syslinux - Jul 2016 - PXELINUX: lpxelinux.0 configuration

Hi all,

I try to switch from pxelinux.0 to lpxelinux.0 as a PXE boot loader. 
With pxelinux.0 I am able to boot my Linux kernel and initrd without any 
problems.

When I change DHCP option 67 to lpxelinux.0 this file gets loaded via 
TFTP. On the client screen I see the welcome message (PXELINUX 6.03 lwIP 
?) but nothing more. Sniffing revealed that there are no further 
attempts to load anything.

I expected lpxelinux.0 to load the same configuration file as 
pxelinux.0, either by TFTP or HTTP.
This is from my default config file:
KERNEL http://172.16.0.96/boot/vmlinuz
APPEND initrd=http://172.16.0.96/boot/initrd

What am I missing? Do I have to set any further DHCP options?

Greetings
Christof

On Tue, Jul 5, 2016 at 2:16 AM, Christof B?ckler <syslinux at zytor.com>
wrote:
> Hi all,
>
> I try to switch from pxelinux.0 to lpxelinux.0 as a PXE boot loader. With
> pxelinux.0 I am able to boot my Linux kernel and initrd without any
> problems.
>
> When I change DHCP option 67 to lpxelinux.0 this file gets loaded via TFTP.
> On the client screen I see the welcome message (PXELINUX 6.03 lwIP ?) but
Version 6.03.  Is this a distribution build or fresh from the
binary/source archive from kernel.org without any running of 'make'?
> nothing more. Sniffing revealed that there are no further attempts to load
> anything.
Where/how are you sniffing?  I'm guessing from the system with the
tftpd?  pxelinux.0 and lpxelinux.0 should both load ldlinux.c32 next
then try for configuration file.  Which file was last attempted?  What
file was last successful?  Do you see pxelinux.0 loading ldlinux.c32?
> I expected lpxelinux.0 to load the same configuration file as pxelinux.0,
> either by TFTP or HTTP.
> This is from my default config file:
> KERNEL http://172.16.0.96/boot/vmlinuz
> APPEND initrd=http://172.16.0.96/boot/initrd
I'm guessing this is but one LABEL within your config that you're
hoping to load.


# UI menu.c32
# don't use DEFAULT for menu
DEFAULT linux-http
PROMPT 1

LABEL linux-http
  LINUX http://172.16.0.96/boot/vmlinuz
  APPEND initrd=http://172.16.0.96/boot/initrd

LABEL linux
  LINUX vmlinuz
  APPEND initrd=initrd


> What am I missing? Do I have to set any further DHCP options?
Nope.  There's a chance you have a deaf client or one that doesn't
properly report interrupt status.
> Greetings
> Christof
-- 
-Gene

Hi Gene,

Am 05.07.2016 um 12:42 schrieb Gene Cumm:
> Version 6.03.  Is this a distribution build or fresh from the
> binary/source archive from kernel.org without any running of
'make'?
it's actually a freshly downloaded lpxelinux.0 from kernel.org. I get:
$ md5sum lpxelinux.0
d77a175ea1a0a8c05b315d179992e1bd  lpxelinux.0
>> nothing more. Sniffing revealed that there are no further attempts to
load
>> anything.
>
> Where/how are you sniffing?  I'm guessing from the system with the
> tftpd?  pxelinux.0 and lpxelinux.0 should both load ldlinux.c32 next
> then try for configuration file.  Which file was last attempted?  What
> file was last successful?  Do you see pxelinux.0 loading ldlinux.c32?
I am sniffing old school with a hub right next to the thin client.

With pxelinux.0 everything works fine: DHCP request and ACK, ARP request 
and reply, pxelinux.0 gets loaded, ldlinux.c32 and the pxelinux.cfg/* 
files as well, and finally vmlinuz and initrd get downloaded.

It's strange that after the same start (DHCP request and ACK, ARP 
request and reply) lpxelinux.0 gets loaded and then follows an 
(unnecessary) gratuitous ARP for the client IP (172.16.12.1) plus an 
unanswered (!) second ARP request for the server's IP (172.16.0.96). No 
further network traffic is send out by the client.
>
>> I expected lpxelinux.0 to load the same configuration file as
pxelinux.0,
>> either by TFTP or HTTP.
>> This is from my default config file:
>> KERNEL http://172.16.0.96/boot/vmlinuz
>> APPEND initrd=http://172.16.0.96/boot/initrd
>
> I'm guessing this is but one LABEL within your config that you're
> hoping to load.
Yes, this is the full file:

TIMEOUT 0
DEFAULT default
DISPLAY product.txt
LABEL default
         KERNEL http://172.16.0.96/boot/vmlinuz
         APPEND initrd=http://172.16.0.96/boot/initrd [?]
#       SAY Hallo
>> What am I missing? Do I have to set any further DHCP options?
>
> Nope.  There's a chance you have a deaf client or one that doesn't
> properly report interrupt status.
As said, with pxelinux.0 this client is booting up flawlessly. Strange.

Greetings
Christof