bootp and ignore dhcp?

Scott Moser smoser at brickies.net
Mon Jul 30 15:10:41 UTC 2007


On Fri, 27 Jul 2007, Chuck Anderson wrote:
> On Fri, Jul 27, 2007 at 03:37:13PM -0400, Scott Moser wrote:
>> On Fri, 27 Jul 2007, Lars Jacobsen wrote:
>>     I was hoping to get the server to only respond to bootp requests, and
>> ignore all dhcp requests.  I don't own the network, and thus any dhcp
>> responses on it (even to the clients I knew about) can be problematic.
>> I'd rather they get their dhcp responses only from the official dhcp
>> server, not me.
>
> This is an unrealistic goal.  DHCP is based on the BOOTP packet format
> and uses the same transport layer identifiers, so there is no real way
> to separate the functionality of the two on the same network subnet.
> There may be hackish ways to do it, but I wouldn't recommend it.

I somewhat expected this response.  And it mostly makes sense.  What is
confusing to me, is that there are 2 keywords accepted to "allow, deny,
ignore":
   - booting (SV_ALLOW_BOOTING)
   - bootp (SV_ALLOW_BOOTP)

In the source code, one never occurs without the other.  In dhcp-4.0.0a2
their only occurances are in server/bootp.c and server/dhcp.c.  So as far
as I can see, while these are documented differently (leading me to
believe that I could do what I wanted), these 2 options do the same
thing.  The only differences being the error messages that are logged.
It is entirely possible that I'm missing something in reading of the
source code.

    Thanks for responses on this.  I do appreciate them.  I'm sorry if
I'm misunderstanding something obvious.  If I am, please point it out to
me.


More information about the dhcp-users mailing list