[Kea-users] Need Help Overriding Standard Option in Kea DHCPv4

[Dipesh Kayastha]

Hi Kea Dev Team,

I’m migrating from ISC DHCP to Kea and encountered an issue when attempting
to define a custom option using code 121. In ISC DHCP, I was able to define
option 121 for custom use as follows:

option custom-option-121 code 121 = array of integer 8;

In Kea, when I try to replicate that using:

"option-def": [
  {
    "name": "custom-option-121",
    "code": 121,
    "type": "uint8",
    "array": true

  }
]

I get the following error:
DHCP4_PARSER_FAIL failed to create or run parser for configuration element
option-def: unable to override definition of option '121' in standard
option space 'dhcp4'


I understand from the Kea ARM documentation (
https://kea.readthedocs.io/en/latest/arm/dhcp4-srv.html#id5) that Option
121 is already part of the standard DHCPv4 option definitions. However, in
my use case, I need to send custom data under option 121 because the client
expects it.

Is there a supported way in Kea to:

   1.

   Override standard options like 121 with custom format/data?
   2.

   Send custom data using option 121 in a way compatible with clients
   expecting it?

Any advice or suggested workarounds would be greatly appreciated.
Note that this is not only for option 121, I am also using other option
numbers also as custom option.

Best regards,
Dipesh
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