[gPXE] gpxe 1.0.0 chainloading and disabling use-cached to make new second dhcp request

[Pasi Kärkkäinen]

On Fri, Sep 17, 2010 at 02:59:11PM -0400, Joshua Oreman wrote:
> On Fri, Sep 17, 2010 at 2:52 PM, Pasi Kärkkäinen <pasik at iki.fi> wrote:
> > Any ideas?
> 
> Setting use-cached to zero in the DHCP packet won't override
> gpxelinux.0's default setting it to 1.
> 

Thanks for the reply!

I guess the default value for use-cached was changed at some point?
I found many docs indicating the default value is 0 ..
Those seemed to be old info..

> Sending a different filename to gpxelinux.0 won't actually do
> anything; gpxelinux.0 always runs its embedded PXELINUX. So you
> actually need to set PXELINUX-specific option 209/210 (configuration
> file path) in the original DHCP packet. There's more information on
> this available in the PXELINUX documentation. 
>

This was the trick. I specified "pxelinux.pathprefix" and 
now gPXE loads "pxelinux.cfg/<mac-address>" cfgfiles over http!


> You should have no need to do the busid check in dhcpd.conf.
> 

I guess things have changed.. pretty much every tutorial/example
I could find said I need to use "bus-id" check to configure
gpxelinux specific settings.. 

Oh well :)

Thanks again for the quick reply. This is the dhcpd.conf I'm using now:

-----------------------------------------------------------------------

ddns-update-style interim;
ignore client-updates;

allow booting;
allow bootp;

option space pxelinux;
option pxelinux.magic      code 208 = string;
option pxelinux.pathprefix code 210 = text;

class "pxeclients" {
	match if substring(option vendor-class-identifier, 0, 9) = "PXEClient";
	next-server 10.0.0.1;
  
	site-option-space "pxelinux";
	option pxelinux.magic f1:00:74:7e;
        if exists dhcp-parameter-request-list {
		# Always send the PXELINUX options (specified in hexadecimal)
		option dhcp-parameter-request-list = concat(option dhcp-parameter-request-list,d0,d1,d2,d3);
	}

	option pxelinux.pathprefix "http://10.0.0.1/gpxe/";
	filename "/gpxelinux.0";
}

subnet 10.0.0.0 netmask 255.255.255.0 {
        option routers                  10.0.0.1;
        option subnet-mask              255.255.255.0;
        option domain-name              "pxeboot.loc";
        option domain-name-servers      dnsip1,dnsip2;
        range dynamic-bootp             10.0.0.20 10.0.0.200;
        default-lease-time              21600;
        max-lease-time                  43200;
}