[Kea-users] leasequery and PD reservations

[Tomek Mrugalski]

W dniu 15.02.2017 o 15:37, Torbjörn Eklöv pisze:
> Thanks. I get remote-id and client-id in the log now but there are more issues that prevents me from using it in production.
> I miss this now:
Ahhh, new requirements.

> - leasequery
We don't have this planned. It's not a frequently requested feature by
any means. It's unlikely leasequery would be implemented in a near
future, unless there are people who are willing to step up and fund its
development.

Also, there are now 3 types of leasequery protocols defined right now. I
presume you're talking about the "basic" one, right?

For completeness, here are the RFCs that define them:

1. RFC5007 - DHCPv6 Leasequery (requestor asks about specific address or
about specific identifier and gets one reply, works over UDP)

2. RFC5460 - DHCPv6 Bulk Leasequery (requestor can get many responses,
e.g. give me all clients that connected through relay X, works over TCP)

3. RFC7653 - DHCPv6 Active Leasequery (requestor subscribes to the
server, and then the server sends any lease updates as soon as they
happen, works over TCP or TLS)

> - lease database where I assign PD prefix depended on client-id and remote-id
I recall similar request was discussed previously, but I reviewed my
mail archive and can't find it. Anyway, here it is:

Reservations are stored in a separate table, so they're not exactly the
same as "lease database". Those can be kept in MySQL, PostgreSQL or in
the config file. (There's also an unreviewed patch for Cassandra, but I
would recommend against doing anything with it in production).

For any given client, do you need both client-id and remote-id? If yes,
that's not supported. If you can do a reservation by client-id OR
remote-id, there is something you can try. PD can be reserved for
client-id (use "duid" keyword). PD can also be reserved for specific
hardware address (use "hw-address" keyword) and configure your MAC
source to use treat content of remote-id as MAC.
See Section 8.3
(https://jenkins.isc.org/job/Kea_doc/guide/kea-guide.html#host-reservation-v6)
and Section 8.9
(https://jenkins.isc.org/job/Kea_doc/guide/kea-guide.html#mac-in-dhcpv6).

Implementing more reservation types is one of the strong candidate
features for upcoming 1.3. However, the decision hasn't been made yet.
Mid to late March sees to be the timeframe to scope features for 1.3.

> Does anyone on this list know a product that can do what I want? ISC DHCP and Dibbler don’t
Forget about Dibbler. It was a hobby project I did over weekends, but it
isn't maintained. I did that for 13 years, but I simply don't have time
for that any more.

Depending if the hw-address+mac-sources trick works for you, you may be
missing leasequery only. Or perhaps leasequery and the reservation stuff
if the trick doesn't cover your case. One of the things we consider for
1.3 is a generic reservation mechanism. You'd define an expression in a
way similar to client classification and use values of that expression
in your reservations.

It seems the biggest problem here is leasequery. So how badly do you
need it?

Tomek