[Kea-users] DHCPv6 option 16 and built in client class

[Xuo Guoto]

Thanks for your reply, Darren.

I have been trying different approaches to get client class working with DHCPv6.


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------- Original Message -------
On Friday, December 2nd, 2022 at 5:57 AM, Darren Ankney <darren.ankney at gmail.com> wrote:


> I don't presently have DHCPv6 setup in my home network, but my kea
> server for DHCPv4 seems to be assigning the clients to the vendor
> classes:

Yes, I also have DHCPv4 working correctly.

I attempted to define a client-class to manually match the packet and assign a class:

    "client-classes": [
      { 
        "name": "dhv6_pool_class",
        "test": "substring(option[16].hex,6,15) == 'dhv6_pool'"
      }

Logs indicate that this is getting matched

2022-12-06 12:37:33.051 EVAL_DEBUG_OPTION Pushing option 16 with value 0x000096D70009646876365F706F6F6C
2022-12-06 12:37:33.051 EVAL_DEBUG_STRING Pushing text string '6'
2022-12-06 12:37:33.051 EVAL_DEBUG_STRING Pushing text string '15'
2022-12-06 12:37:33.051 VAL_DEBUG_SUBSTRING Popping length 15, start 6, string 0x000096D70009646876365F706F6F6C pushing result 0x646876365F706F6F6C
2022-12-06 12:37:33.051 EVAL_DEBUG_STRING Pushing text string 'dhv6_pool'
2022-12-06 12:37:33.051 EVAL_DEBUG_EQUAL Popping 0x646876365F706F6F6C and 0x646876365F706F6F6C pushing result '
true'
2022-12-06 12:37:33.051 EVAL_RESULT Expression dhv6_pool_class evaluated to 1

In https://kea.readthedocs.io/en/kea-2.2.0/arm/classify.html#classification-steps item 3 states that:

<quote>
Classes with matching expressions and not marked for later evaluation (“on request” or depending on the KNOWN/UNKNOWN built-in classes) are processed in the order they are defined in the configuration; the boolean expression is evaluated and, if it returns true (a match), the incoming packet is associated with the class.
</quote>

Here the expression matches and is true.

2022-12-06 12:37:33.052 DHCP6_CLASS_ASSIGNED duid=[00:03:00:01:02:00:00:00:00:01], tid=0x147866: client packet has been assigned to the following class(es): UNKNOWN

but packet is not assigned to that class.

I have been pulling out my hair for past couple of days on this, anyone with a working config to get this done would be very helpful

X.