One DHCP Server, Multiple routed subnets, roaming clients

Simon Hobson dhcp1 at
Tue Oct 27 18:59:52 UTC 2009

James Jalbert wrote:

>I have a DHCP server in my main building. This building also 
>connects to 6 other building through a WAN. I have one DHCP Server 
>(Ubuntu server9.04, DHCP 3.1) with multiple subnet decelerations, 
>and one large host file, added with an include. Everything works 
>great. I have machines that roam between buildings, and as long as I 
>use comma separated fixed address, everything works great.
>Now I would like to be able to set up the server so that, if a 
>machine has a deceleration with a fixed address, but is requesting 
>an ip form another building, it would be assigned a dynamic address, 
>however if there is no Host deceleration(an unknown client) it will 
>not be assigned any address.

Try this :

   pool {
     range .... ;
     allow known clients;

If a client doesn't have a host declaration then it is not known, and 
will be denied a lease. If it does have a host declaration then it is 
known, and will get a dynamic address (unless it has a fixed address 
valid in the subnet).

Simon Hobson

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