[Kea-users] Migrating from ISC DHCP

[Francis Dupont]

Tomek Mrugalski writes:
> > 3. isc style if statements in subnets. 
> > --------------------------------------
> > 
> > We currently add specific options to replies in specific subnets only
> > depending on further criteria like firmware version supplied in other
> > options.
> > 
> > I started thinking about implementing this in KEA with classes and 
> > matching those classes in host reservations included into the 
> > specific sunets.  Would that work ?  Is my requirement clear enough 
> > ?
> While the exact logic behind if statement does not have direct
> replacement in Kea, there are things you could do.
> 
> Keep in mind that the client-classes in reservations means that the
> client is automatically assigned to said class if its identifier
> matches. This would work if you have host reservations for all clients
> (you mentioned customer CPE identification, so I presume you have). One
> limitation is that currently client classes are global.
> 
> You can specify client-class on per subnet basis, but that is used for a
> different purpose. It prevents clients that do not belong to a class
> from even using a subnet. It's useful to remember the order in which Kea
> does its operation:
> 
> 1. packet is being classified (global client-classes are applied)
> 2. subnet selection is conducted (classes assigned in step 1 may affect
> this step)
> 3. lease is selected from the subnet. If a client has a reservation in
> this subnet, it is being used. If that reservation contains
> client-classes, the packet is being assigned to that class.
> 4. options being added, possibly based on the class information.

=> when the shared network feature will be available in Kea I believe
we (*) should be able to translate this usage of ISC DHCP classes into
a Kea config (today it works only in cases where no pool is used in
more than one translated subnet/subnet+class entry).

Regards

Francis Dupont <fdupont at isc.org>

PS (*): "we" is in fact a migration tool, i.e., a piece of code.