Two subnets, one with PXE clients

Simon Hobson dhcp1 at
Wed Mar 3 16:59:25 UTC 2010

Osmany wrote:

>Now the PXE Client boots perfectly with the IP it's meant
>to have, but now I have another problem. Once the PXE client loads, it
>begins configuring itself to load the OS and obviously does a
>DHCPDISCOVER once again because it is no longer a PXE Client but I find
>that the dhcp server assigns an IP from the subnet which I
>don't want it to have those IPs because the LTSP server does not have
>any of those IP's.

Well of course, that's exactly how you've configured it !

Once the client boots it's OS, it's not a PXE client, doesn't match 
the PXE class, and so is only allowed an IP from the 
subnet. If you want certain clients to continue getting a address after boot, then you'll need to add a class 
that matches them, and add the appropriate allow/deny statements.

Eg :

class "LTSPClients" {
   match if ...

shared-network ... {
   subnet netmask {
       allow unknown-clients;
       deny members of "PXEClients";
       deny members of "LTSPClients";

   subnet netmask {
       allow members of "PXEClients";
       allow members of "LTSPClients";

The next issue you may find, at least if you boot Windows clients, is 
that if the client supplies a Client-ID then it will be considered a 
different client and would still be given a different IP. This is a 
well known 'problem', and I believe there is finally a means of 
getting round it without patching the source in the latest version 
4.2.0a ?

Simon Hobson

WANTED: "Software CD ROM Kit" for Canon CLBP 360-PS printer (Canon 
part no RH6-3612, or possibly RH6-3810, or RH6-3610 might do). I've a 
dead HD and need this CD so I can replace the disk and re-install the 
printer OS on it.
This is NOT the same thing as the printer drivers to load on the 
computer - there's no problem there.
If anyone knows where I might get hold of one I'd be grateful - 
requests to Canon drew a blank, it's been out of support for years.
Alternatively, if anyone has one of these and would let me image 
their hard disk ...

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