Hi, "ddns-qualifying-suffix" is not a parameter that will enable or disable ddns updates. Your server will not use the "domain-name" option content that you set in the configuration to create a name either. It will use that which is set in "hostname" in a reservation as an FQDN, it seems, though I've never tried it. See here: https://kea.readthedocs.io/en/stable/arm/dhcp4-srv.html#reserving-a-hostname where it says:
"If the ddns-qualifying-suffix is not specified, the default (empty) value will be used, and in this case the value specified as a hostname will be treated as a fully qualified name. Thus, by leaving the ddns-qualifying-suffix empty it is possible to qualify hostnames for different clients with different domain names:" What actually happens is a matter of the rules that were set in the behavioral parameters as described here: https://kea.readthedocs.io/en/stable/arm/dhcp4-srv.html#ddns-for-dhcpv4 Clients may update DNS themselves, the server may update DNS, no one may update DNS, or the server can enforce its own updates over the client's wishes. In addition, part or all of the FQDN may be replaced. This part even has implications outside of DDNS (what is returned to the client in the DHCP response, for example). Thank you, Darren Ankney On Thu, Jan 1, 2026 at 9:43 AM lejeczek via Kea-users <[email protected]> wrote: > > Hi guys. > Is it possible to make KEA do DDNS this way > .... > "dhcp-ddns": { > "enable-updates": true > }, > .... > "subnet4": [ > { > "id": 1, > "subnet": "10.3.0.0/22", > "ddns-override-client-update": false, > "valid-lifetime": 3600, > "max-valid-lifetime": 3600, > "pools": [ > { > "pool": "10.3.1.10 - 10.3.1.20" > } > ], > "option-data": [ > { > "space": "dhcp4", > "name": "domain-name", > "code": 15, > "data": "hub.mine.priv" > }, > .... > "reservations": [ > { > "hostname": "cromo", > "hw-address": "52:54:00:74:5b:08", > "option-data": [ > { > "space": "dhcp4", > "name": "domain-name", > "code": 15, > "data": "private.way" > }, > ] > //"client-classes": [ "PRIVATE.ROAD" ] > }, > .... > > ddns-qualifying-suffix is absent, I read somewhere that in it's absence > domain-name is used for DDNS then. > I'm hoping that subnet will do DDNS with one domain and if a client has > reservation with another domain, then such "reserved" domain will be used, > but.. > KEA with such config is not doing DDNS at all I think - does that make sense > & is what I'm hoping for possible? > > many thanks, L. > -- > 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] -- 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]
