[Kea-users] DHCPOFFER delay

[Darren Ankney]

Hi Andrey,

I cannot think of a way to accomplish this.  The usual way things like
this are done is that the same subnet is assigned to both relays.  The
client is given a gateway address that is a floating IP between the
two relays (which are also the gateway routers).  In this way, it
doesn't matter which relay sends the traffic to the DHCP server.  The
correct subnet is allocated and routing works.  It sounds like, in
this case, you've assigned separate subnets to the relays ... Kea
won't even know that they are related in any way.  Won't this cause a
temporary customer routing problem if one of the routers dies?

Thank you,
Darren Ankney

On Thu, Nov 7, 2024 at 10:50 AM Andrey Kostin <ankost at podolsk.ru> wrote:
>
> Hi Darren,
>
> I plan to have two DHCP relay routers facing IPoE subscribers and would
> like to make relay selection more deterministic, so that one relay is
> active and another is backup. Currently I assign IPs from different
> subnets to advertise only aggregate prefix for each subnet from each
> router. Users connect to both relays and they work as active-active.
> Seems there is no problem with this setup, but just wanted to know is
> there a way to make one of relays preferred.
>
> Kind regards,
> Andrey
>
> Darren Ankney писал(а) 2024-10-31 04:18:
> > Hi Andrey,
> >
> > There is no way to do this that I am aware of.  Kea is designed to be
> > fast.  There are many ways to influence what subnet is selected,
> > however.  Perhaps some detail about what you are trying to do might
> > reveal another idea for a solution?
> >
> > Thank you,
> > Darren Ankney
> >
> > On Mon, Oct 28, 2024 at 3:41 PM Andrey Kostin <ankost at podolsk.ru>
> > wrote:
> >>
> >>
> >> Hello, Kea users,
> >>
> >> A quick question: is there a way to set a delay for DHCPOFFER sent by
> >> kea-dhcp4 or kea-dhcp6 via relay to make clients to use one
> >> relay/subnet
> >> over another?
> >>
> >> Kind regards,
> >> Andrey
> >> --