[Dibbler] question

Tomasz Mrugalski thomson at klub.com.pl
Thu Mar 17 21:22:43 CET 2005

On Wed, 16 Mar 2005 somebody known as wario super wrote:

> Hi,
Sorry for replying with such delay, but I was out for one day.

> I'm trying to configure an IPv6 network. I have two sub networks one 
>with 2001:1:0:1::/64 and one with 2001:2:0:1::/64. All the networks are 
>connected to the same router interface (the interface has two different 
>IPv6 adresses one for each sub network: 2001:1:0:1::10 and 
> Actually the router is a computer running dibbler for dhcp.

I'm not sure if I understood well. You want server support for 2 
different IP classes on the same link, right? If that is so, how do you 
want to decide, which client should get address from which class?

> Is it possible to configure the clients and the server in order to have 
>automatic address configuration for the computers in the sub network 1 
>AND in the sub network 2.
Theoretically it is possible. This feature was coded, but was never 
tested. It would be great if you could test it and send results. If you do 
that, I promise I'll quickly fix all reported bugs to make this feature 
work :)

You should define 2 classes. But there is a problem. Server will assign 
addresses from the first class. Since this class will never run out of 
addresses, all clients will get address from class 1. To avoid this, you 
can use "reject-client" or "accept-only" directives. Both directives 
support DUIDs of link-local addresses. This will allow to assign some 
clients to the second class.

Here's example server.conf:

log-level 8
log-mode short

iface eth0 {
  T1 1000
  T2 2000

  class {
    pool 2001:1:0:1::1-2001:1:0:1:ffff:ffff:ffff:ffff
    accept-only fe80::0-fe80::0800:0000:0000:0000
  class {
    pool 2001:2:0:1::1-2001:2:0:1:ffff:ffff:ffff:ffff


This accept-only range might require some tweaking.

Hope that helps. I suppose this is rather workaround than real problem 
solution. I think that server could randomly assign addresses from all 
defined classs, not just from the first one. What do you think about this?

Tomasz Mrugalski,              | "I think there is a world market for     |
thomson(at)klub(dot)com(dot)pl |  about five computers."                  |
                                |     Thomas J. Watson (Chairman, IBM) 1943|

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