We are attempting to setup an automated system to build some Linux
systems. We have utilised the PXELINUX bootloader after encountering
the PXE 512Kb limit with bootp.
We now have another issue which you may have already run into. In the
DHCP configuration we specify pxelinux.0 as the bootfile, this works
reasonable well, we call the Redhat vmlinuz and initrd.img files
within the pxelinux.cfg/config file and the installation begins
as expected. We would like to have a non-interactive installation
using the Kickstart mechanism to provide the responses, the issue
is that the installer expects to get the Kickstart file location
from the DHCP 'bootfile' parameter which we have already used
to provide the pxelinux.0.
Have you encountered this problem before?
Thanks in advance for any assistance you can provide.
Peter Guthrie
-- 
      ______          ____________________________________________       
     /_____/\ 
    /____ \\ \        Peter Guthrie, Project Engineer 
   /_____\ \\ /       Customer Ready Systems
  /_____/ \/ / /      Sun Professional Services EMEA
 /_____/ /   \//\     Sun Microsystems   
 \_____\//\   / /     Linlithgow, West Lothian, EH49 7LR, Scotland.
  \_____/ / /\ /      Tel:      +44 (0)1506-673014 (Int. x73014)      
   \_____/ \\ \       Mobile:   +44 (0)7796-274682
    \_____\ \\        Fax :     +44 (0)1506-672150
     \_____\/         mailto:Peter.Guthrie at sun.com 
                      ____________________________________________
> We are attempting to setup an automated system to build some Linux > systems. We have utilised the PXELINUX bootloader after encountering > the PXE 512Kb limit with bootp. > > We now have another issue which you may have already run into. In the > DHCP configuration we specify pxelinux.0 as the bootfile, this works > reasonable well, we call the Redhat vmlinuz and initrd.img files > within the pxelinux.cfg/config file and the installation begins > as expected. We would like to have a non-interactive installation > using the Kickstart mechanism to provide the responses, the issue > is that the installer expects to get the Kickstart file location > from the DHCP 'bootfile' parameter which we have already used > to provide the pxelinux.0.Easy enough, though nothing to do with pxelinux as such. PXE always has a 2 stage start up - when using pxelinux as the NBP, the 2nd stage gets the config via tftp, so there are no confusing multiple dhcp requests, but if a subsequent stage uses dhcp, you need to tell the dhcp server that replies to requests from PXE firmware have different contents from the replies to other clients. Etherboot uses dhcp rather than tftp, so to use Etherboot as a PXE NBP, one must always differentiate the PXE and Etherboot dhcp requests from each other (and those of Kickstart or Linux kernel). Requests can be distinguished by Vendor Class ID (this is what the VCI and other class identifiers are for). A "PXEClient" VCI is part of the PXE spec, so you should be able to rely on it. Use ISC dhcpd v3 if you don't already have it (this is possible with v2, but v3 is better). If the Kickstart request doesn't include a VCI the kickstart values will need to be the "no VCI" default (and Red Hat should fix this). You can see the request contents with log statements in the dhcpd config - look at the dhcpd docs. For an example, look at http://www.ltsp.org/documentation/pxe.howto.html - this differentiates PXE from Etherboot, rather than Kickstart, but the principle is similar. Read http://www.stanford.edu/~alfw/PXE-Kickstart if you haven't already.
You need to put the unique kickstart file on a NFS share and reference it. In your config files under pxelinux.cfg, you should make something like this (the append should all be one line). default ks display boot.msg label ks kernel vmlinuz append initrd=initrd.img lang= devfs=nomount ramdisk_size=7168 ks=nfs:10.1.1.1:/kickstart_files/my_unique_kickstart_file James Martin, RHCE Peter Guthrie wrote:> > We are attempting to setup an automated system to build some Linux > systems. We have utilised the PXELINUX bootloader after encountering > the PXE 512Kb limit with bootp. > > We now have another issue which you may have already run into. In the > DHCP configuration we specify pxelinux.0 as the bootfile, this works > reasonable well, we call the Redhat vmlinuz and initrd.img files > within the pxelinux.cfg/config file and the installation begins > as expected. We would like to have a non-interactive installation > using the Kickstart mechanism to provide the responses, the issue > is that the installer expects to get the Kickstart file location > from the DHCP 'bootfile' parameter which we have already used > to provide the pxelinux.0. > > Have you encountered this problem before? > > Thanks in advance for any assistance you can provide. > > Peter Guthrie >
the location of the kickstart file is derived from a kernel commandline
argument, not from a dhcp response.  for example,
LABEL ks73
    KERNEL vmlinuz-7.3-bootnet
    APPEND initrd=initrd-7.3-bootnet.img ip=dhcp
ks=nfs:192.168.99.1:/path/to/ks.cfg lang= text devfs=nomount ramdisk_size=7168
Jim Wright, Senior Engineer
Tel: 415-358-2609   Fax: 415-358-2646   Toll Free: 888-PENGUIN
PENGUIN COMPUTING - www.penguincomputing.com
On Wed, 4 Sep 2002, Peter Guthrie wrote:
> 
> We are attempting to setup an automated system to build some Linux
> systems. We have utilised the PXELINUX bootloader after encountering
> the PXE 512Kb limit with bootp.
> 
> We now have another issue which you may have already run into. In the
> DHCP configuration we specify pxelinux.0 as the bootfile, this works
> reasonable well, we call the Redhat vmlinuz and initrd.img files
> within the pxelinux.cfg/config file and the installation begins
> as expected. We would like to have a non-interactive installation
> using the Kickstart mechanism to provide the responses, the issue
> is that the installer expects to get the Kickstart file location
> from the DHCP 'bootfile' parameter which we have already used
> to provide the pxelinux.0.
> 
> Have you encountered this problem before?
> 
> Thanks in advance for any assistance you can provide.
> 
> Peter Guthrie
> 
> -- 
>       ______          ____________________________________________       
>      /_____/\ 
>     /____ \\ \        Peter Guthrie, Project Engineer 
>    /_____\ \\ /       Customer Ready Systems
>   /_____/ \/ / /      Sun Professional Services EMEA
>  /_____/ /   \//\     Sun Microsystems   
>  \_____\//\   / /     Linlithgow, West Lothian, EH49 7LR, Scotland.
>   \_____/ / /\ /      Tel:      +44 (0)1506-673014 (Int. x73014)      
>    \_____/ \\ \       Mobile:   +44 (0)7796-274682
>     \_____\ \\        Fax :     +44 (0)1506-672150
>      \_____\/         mailto:Peter.Guthrie at sun.com 
>                       ____________________________________________