ISC DHCP server offers fixed IP addresses to ANY device!

Frode Nordahl frode at
Fri Jan 30 00:26:41 UTC 2009

On 29. jan.. 2009, at 18.57, David W. Hankins wrote:

> On Thu, Jan 29, 2009 at 10:21:53AM +0100, Frode Nordahl wrote:
>> We are about to start using the reserved lease functionality, and  
>> bumped
>> into this issue. I did not find any public CVS or patches for this  
>> online,
>> so I wrote my own while waiting. :-)
> Can you bounce it to dhcp-bugs at  I'll see if I can review it
> into next maint.

Done,  ISC-Bugs #19274

>> We are setting the reserved flag through OMAPI by sending flags  
>> with a char
>> (1 byte) value set to 0x04. The support for this seems to be a bit
>> undocumented at the moment, will we get burned in the future for  
>> doing
>> this? :-)
> Now that you are an OMAPI user, you will burn for all eternity.

LOL! :-)

> Well, maybe it's not quite that bad.  I've never liked how OMAPI was
> built, the way it requires the client end to know details of the
> server's memory structures.
> There is a small bit of heat in your future as, after we have a
> replacement with more symbolic abstracts (my thinking is still XML),
> we'll be migrating away from it.  I like to think you'll /want/ to
> migrate, but we'll see how popular it is.

OMAPI shows signs of being treated like a stepchild for some time, and  
I agree that the protocol is too complex to be easilly incorporated in  
end-user applications.

To get around this I am currently using homegrown middle-ware written  
in C (only usefull way to talk OMAPI) that talks XML (SOAP) with  
client software written in languages such as PHP.

So we welcome this change, just give us some time to adapt :-)

> I know a lot of people use OMAPI because it's the only game in DHCP's
> town, so we try not to shake it up too badly even between feature
> releases.

Exactly, after having spent some time with ISC DHCPD source code, it  
seems to me that omapi is anchored pretty well internally in ISC DHCPD.

So I suspect that making a transition by supporting both OMAPI and the  
new API externally would not be impossible ?

Frode Nordahl

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