[CentOS] how to debug pxe boot problems

Tue Apr 13 06:55:43 UTC 2010
Rudi Ahlers <rudiahlers at gmail.com>

Hi all,

I'm  trying to get a pxeboot server up and running, according to the
instructions on the WIKI (http://wiki.centos.org/HowTos/PXE/PXE_Setup
& http://wiki.centos.org/HowTos/PXE/PXE_Setup/Menus)

Here's my /tftpboot/pxepxelinux.cfg/default :

default menu.c32
prompt 1
timeout 300


label Dos Bootdisk
        MENU LABEL ^Dos bootdisk
        kernel memdisk
        append initrd=images/622c.img

LABEL CentOS 5 x86_64
        MENU LABEL ^CentOS 5 x86_64
        kernel images/centos/5/x86_64/vmlinuz
        append initrd=images/centos/5/x86_64/initrd.img
ramdisk_size=100000 ksdevice=eth0 ip=dhcp url --url

label linux
        kernel vmlinuz
        append initrd=initrd.img ramdisk_size=9216 noapic acpi=of

Then, here's the layout for the CentOS 5 image:

[root at intranet /]# ll /tftpboot/images/centos/5/
total 0
lrwxrwxrwx 1 root root 35 Apr 13 07:20 x86_64 ->

As you can see, I linked the folder to a Linux image on the hard
drive. Apache then advertises that folder on the LAN as follows: and I can browse the
folders via Firefox.

Yet when I bootup a PC in PXE mode, it doesn't actually load the
CentOS image. I can see the PXE Menu and choose between "Dos
Bootdisk", "CentOS 5 x86_64" and "linux" (which I setup as a test).
When I load "Dos Bootdisk", I get an error:

Loading memdisk....
Could not find ramdisk image:images/622c.img
boot :

So, it's reading the configuration, but not loading the CentOS boot
image. /var/log/messages doesn't give my any errors on this (yes I
know how to read /var/log/messages)
Does anyone know how to get pxeboot to output debug messages to
syslog?  OR,what am I doing wrong?  The tutorials I got on the net are
rather vague on this. And please don't tell me to use Cobbler, I
already tried that but no one one this lists supports it.

Kind Regards
Rudi Ahlers

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