lease problem

Simon Hobson dhcp1 at
Sat Jul 28 07:23:20 UTC 2012

Julie Xu wrote:

>I  get complain about new machines. the problem is :
>       when new machine come online first time, it get one ip 
>address. when the machine reinstall company image and reboot, even 
>it is in 10 minutes time, it get another ip address.

let me guess, the company image is Windows, and the <something else> 
booted before that is not Windows ?

It's most likely that the first system booted does not send a 
Client-ID - this is the default for pretty much everything other than 
Then when the system is booted with Windows, a Client-ID is used.

The ISC server uses the Client-ID as the primary database key if one 
is supplied, and only falls back to the MAC (hardware) address if 
there is no Client-ID. So the two systems are different clients as 
far as the server is concerned.

There used to be some patches that would "fix" this, but I've not 
heard of them for a while and I've no idea if they are maintained. If 
not maintained, they wouldn't work (I assume) against the current 

But the obvious question is does it actually matter ?

Simon Hobson

Visit for books by acclaimed
author Gladys Hobson. Novels - poetry - short stories - ideal as
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