[Kea-users] Ddns not Updated when hostname is assigned via hw-address when using hook libdhcp_ddns_tuning.so

[Peter Davies]

Hi Joop,
     A host reservation should have an identifier. If you do not use the 
"hw-address,"
what identifier do you use?

You may wish to use the following, which appends the IP address to the 
hostname:
                 "hostname-expr" : 
"concat('vm-test-',addrtotext(option[50].hex))" } }

/Peter


On 05/01/2026 16.59, Joop Boonen wrote:
> Dear all,
>
> I'm using the option like this.
> "Dhcp4": {
>      "hooks-libraries": [
>          {
>              "library": "libdhcp_ddns_tuning.so",
>              "parameters": {
>                  "hostname-expr" : "concat('vm-
> test-',hexstring(option[50].hex,''))"
>              }
>          },
>
> I notice when I don't have an hw-address entry
>
>
>                  {
>                      "hw-address": "<hw-addres>",
>                      "ip-address": "<ip-address",
>                      "hostname": "<hostname>"
>                  },
>
> The ddns entries doesn't get Updated.
> For some reason it looks like hostname-expr needs an assigned hostname.
>
> Does someone know how this can be solved.
>
> Regards,
>
> Joop Boonen.

-- 
Peter Davies
Support Engineer
Internet Systems Corporation