Pool/Scope or subnet with PXE boot options?

Jason Gerfen jason.gerfen at scl.utah.edu
Fri Oct 9 15:28:32 UTC 2009

Do any of you currently utilize this feature in your dhcpd.conf? If so 
could I perhaps get a syntax example?

The reason I am asking is because I currently maintain a project over at 
sourceforge.net that allows for administrators to manage their 
dhcpd.conf through a series of forms under an authenticated website 
(http://phpdhcpadmin.sourceforge.net) and was recently asked to 
incorporate this functionality outside of the "group" definition for 
static hosts.

My assumption for a correct syntax would be something like the two 
following examples for subnet declarations or for pool declarations:

subnet netmask {
     option domain-name-servers,;
     option routers;
     option ip-forwarding off;
     filename "pxelinux.0";

pool {
    option domain-name-servers,;
    option routers;
    option ip-forwarding on;
    option broadcast-address;
    option ntp-servers time.domain.com;
    default-lease-time 1800;
    min-lease-time 700;
    max-lease-time 3200;
    filename "pxelinux.0";

Any help and specifically examples are appreciated.

Bruce Hudson wrote:
>> a. How does a client request those options?
>> b. I thought all client within the defined scope would receive those 
>>    options.
>     Client requests include a "parameter request list" to ask for the
> options it wants and knows how to deal with. Since it is possible for
> options to run out of room, the server provides those options in the
> order requested. It can provide more options if required but this will
> normally require special configuration.
>     Of course, the "next-server" and "filename" options are fixed fields
> rather than using vendor space so this does not apply to them specifically.
> They should always be included. In general though, as Glen said, a client
> is only given the options requested.
>> c. Wouldn't any client act on the next-server option?
>     How a client responds to anything is largely undefined. Certainly
> including a "next-server" will not force a client to run something 
> like tftp to download a file on its own; at least not in general. 
> --
> Bruce A. Hudson				| Bruce.Hudson at Dal.CA
> ITS, Networks and Systems		|
> Dalhousie University			|
> Halifax, Nova Scotia, Canada		| (902) 494-3405
> _______________________________________________
> dhcp-users mailing list
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Jason Gerfen
Systems Administration/Web application development
jason.gerfen at scl.utah.edu

Marriott Library
Lab Systems PC
295 South 1500 East
Salt Lake City, Utah 84112-0806
Ext 5-9810

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