home | list info | list archive | date index | thread index

Re: [OCLUG-Tech] Re: GCC: Request for help to get cluster booting!

  • Subject: Re: [OCLUG-Tech] Re: GCC: Request for help to get cluster booting!
  • From: Stephen Gregory <oclug [ at ] kernelpanic [ dot ] ca>
  • Date: Fri, 19 Sep 2008 11:54:02 -0400
On Thu, Sep 18, 2008 at 11:54:15PM -0400, Richard Cook wrote:
>
>> Hopefully you will see the pxelinux.0 get loaded, and then pxelinux will
>> grab the default config and load the kernel and initrd.
>
> And ... no.   :(

I am stumped then.

I find it amazing how completely useless the online documentation for
etherboot/gPXE is. After much looking I found this:

> With the most recent EtherBoot releases (as available from
> Rom-O-Matic without the need to compile anything yourself), PXE
> support is compiled in by default. Those ROMs will be able to either
> load bpbatch, PXELinux, any PXE second stage loader, or the
> traditional mknbi-tagged Linux kernels directly.

... and that is about it for howto boot using PXE.


I did find some notes stating that you should use tftpd-hpa as other
tftpd servers don't support PXE properly. Many of those notes were
from 5 years ago though.

A note on dhpcd v3 states that you must specify the next-server in
dhcpd.conf, but your clients seem to be trying to get the pxelinux.0
file so that should not be an issue.


At this point I would cut my losses and use the usb drive(s) to load
the kernel. Using syslinux to load the kernel you can still run the
clients over nfs. If you only have one thumb drive you can remove it
after the kernel is loaded. 

Copy your initrd and vmlinuz images to the thumb drive. Syslinux and
Pxelinux use the same config file format so copy the lines from
pxelinux.cfg/default to the syslinux config file. (Your posted it
earlier. I can't remember the name.)

As you run you machines headless you may want to enable the serial
console. To enable the serial console in syslinux/pxelinux at the
following lines to the config:

SERIAL 0 9600 0
CONSOLE 1

Add the following to the APPEND statement:
 console=ttyS0,9600,n8


Enable the serial console in linux. Under debian and probably most
others edit
/nfsroot/etc/inittab and uncomment the line:
 T0:23:respawn:/sbin/getty -L ttyS0 9600 vt100

Google for Ubuntu. I think you need to add a file to /etc/event.d



> We are on the right track!  It is going for pxelinux.0 but it just does  
> not like it.  :(

Are you using the most recent images from rom-o-matic?


> I copied it from:  /usr/lib/syslinux/pxelinux.0
> What kind of a file is this supposed to be?
> It is not in ELF format; some kind of compressed image?

There is a special PXE format. I think it is raw 386 opcodes.

-- 
sg