How are you doing DHCPv6 ?

Ray Soucy rps at
Mon Jan 23 15:56:58 UTC 2012

This is a problem that would be nice for ISC to resolve (or another
dependable FOSS implementation).

For a while now (about 20 years I believe) we've used ISC DHCPd in a
distributed model for our public IPv4 space.  In a nutshell, each DHCP
server is configured only with static assignments, their log files are
monitored (simple event correlator), and scripts are fired off to
perform tasks like new assignments against a centralized database
(MySQL).  The database is responsible for keeping track of address
assignments centrally and is used to generate configuration files for
DHCPd.  Dynamic updates are made using OMAPI.

Unfortunately, the ISC DHCPv6 implementation makes replicating this
impossible due to the lack of information logged.

Another problem with the ISC DHCPv6 implementation is that it doesn't
allow you to assign fixed-address information based on the DUID _and_
IAID, which becomes a problem when a host has more than one active

The only options are hacking the source code if you feel comfortable
doing so, or waiting for ISC to make the change (if they ever plan

For now, we get by with static assignments made in the database and no
dynamic allocation via DHCPv6, which does OK in a dual-stack
environment where IPv6 isn't considered necessary yet, but in the near
future that will change.

On Tue, Jan 17, 2012 at 5:04 PM, Randy Carpenter <rcarpen at> wrote:
> I am wondering how people out there are using DHCPv6 to handle assigning prefixes to end users.
> We have a requirement for it to be a redundant server that is centrally located. DHCPv6 will be relayed from each customer access segment.
> We have been looking at using ISC dhcpd, as that is what we use for v4. However, it currently does not support any redundancy. It also does not do very much useful logging for DHCPv6 requests. Certainly not enough to keep track of users and devices.
> So, my questions are:
> How are you doing DHCPv6 with Prefix Delegation?
> What software are you using?
> When DHCPv6 with Prefix Delegation seems to be about the only way to deploy IPv6 to end users in a generic device-agnostic fashion, I am wondering why it is so difficult to find a working solution.
> thanks,
> -Randy
> --
> | Randy Carpenter
> | Vice President - IT Services
> | Red Hat Certified Engineer
> | First Network Group, Inc.
> | (800)578-6381, Opt. 1
> ----

Ray Soucy

Epic Communications Specialist

Phone: +1 (207) 561-3526

Networkmaine, a Unit of the University of Maine System

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