Hi Darren, On 11/21/25 4:38 PM, Darren Ankney wrote:
Hello Gregor,Hi Darren, Deciding the reservation model 9.3.9. Global Reservations in DHCPv4 describes in general our setup. Clients generally can roam in our network based on the attributed "pool class" to the specific mac address and the "accessability" of the specific network. The following section: #+begin_quote 9.3.9. Global Reservations in DHCPv4: An address assigned via global host reservation must be feasible for the subnet the server selects for the client. In other words, the address must lie within the subnet; otherwise, it is ignored and the server will attempt to dynamically allocate an address. If the selected subnet belongs to a shared network, the server checks for feasibility against the subnet's siblings, selecting the first in-range subnet. If no such subnet exists, the server falls back to dynamically allocating the address. #+END_quoteThis is generally true, but you are not (as far as I understood) assigning an address to the clients in the reservation and instead are selecting a pool for them to use for a dynamic address with the reservation (by adding the client to one or more classes and using a class guard on the pools).
Generally true - yes - but with the following exception.Again given the following setup. When the host with the mac "a1:bb:cc:dd:ee:ff" visits his "homebase",
subnet id 1 it should be given the "ip-address": "10.0.0.2" and not a pool address.
Should this host however visit, for example subnet id 2, it should be given a pooladdress.
So the the question remains (on this blurry monday morning) - which reservation model should i use?
#+begin_quote
{
"Dhcp4": {
"client-classes": [{
"name": "pool_name_1",
"valid-lifetime": 3600
},
{
"name": "pool_name_etc",
"valid-lifetime": 3600
},
],
"subnet4": [
{
"id": 1,
"subnet": "10.0.0.0/24",
"pools": [
{
"pool": "10.0.0.10-10.0.0.100",
"client-classes": ["pool_name_1",
"pool_name_etc"]
}
],
"reservations": [
{
"hw-address": "a1:bb:cc:dd:ee:ff",
"ip-address": "10.0.0.2",
"client-classes": [ "pool_name_1", "pool_name_etc" ]
},
{
"hw-address": "a2:bb:cc:dd:ee:ff",
"ip-address": "10.0.0.3",
"client-classes": [ "pool_name_etc" ]
}
]
},
{
"id": 2,
"subnet": "192.0.3.0/24",
"pools": [
{
"pool": "192.0.3.10-192.0.3.20",
"client-classes": [ "pool_name_1" ]
},
],
"reservations": [
{
"hw-address": "a1:bb:cc:dd:ee:ff",
"client-classes": [ "pool_name_1", "pool_name_etc" ]
},
{
"hw-address": "a2:bb:cc:dd:ee:ff",
"client-classes": [ "pool_name_etc" ]
}
]
}
]
}
}
#+end_quote
--
Gregor Kling
Abteilung ITS, Sachgebiet ITS-N
Technische Hochschule Mittelhessen
University of Applied Sciences
Tel: 0641/309-1292
E-Mail: [email protected]
smime.p7s
Description: S/MIME Cryptographic Signature
-- ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. To unsubscribe visit https://lists.isc.org/mailman/listinfo/kea-users. [email protected]
