Client with ipv6 pe is not recognized

[godrin]

I'm running pihole on docker with dhcp enabled for ipv4 behind an openwrt-router.

Expected Behaviour:

I have multiple groups and want all client-hosts to be recognized for both ipv4 and ipv6 and do correct filtering.

Actual Behaviour:

I have a single pixel-phone in my environment which is sending DNS-requests solely using its constantly changing (privacy enhanced) IPv6-adresses. In the first run these can't be assigned to a specific mac or host, which shows in the FTL.log:

[2023-04-15 15:12:29.095 267M] Querying gravity database for client with IP fd51:....:e720...
[2023-04-15 15:12:29.096 267M] --> No record for fd51:....:e720 in the client table
[2023-04-15 15:12:29.096 267M] Querying gravity database for MAC address of fd51:....:e720...
[2023-04-15 15:12:29.096 267M] --> No result.
[2023-04-15 15:12:29.097 267M] Querying gravity database for host name of fd51:....:e720...
[2023-04-15 15:12:29.098 267M] --> No result.
[2023-04-15 15:12:29.098 267M] Querying gravity database for interface of fd51:....:e720...
[2023-04-15 15:12:29.099 267M] --> No result.
[2023-04-15 15:12:29.099 267M] Gravity database: Client fd51:....:e720 not found. Using default group.

After some time I get these messages in the log:

[2023-04-15 15:17:25.737 267M] Reloading client groups after 296 seconds (3rd check)
[2023-04-15 15:17:25.737 267M] Querying gravity database for client with IP fd51:....:e720...
[2023-04-15 15:17:25.738 267M] --> No record for fd51:....:e720 in the client table
[2023-04-15 15:17:25.738 267M] Querying gravity database for MAC address of fd51:....:e720...
[2023-04-15 15:17:25.739 267M] --> Querying client table for c8:2a:dd:86:f7:71
[2023-04-15 15:17:25.740 267M] --> Found record for c8:2a:dd:86:f7:71 in the client table (group ID 47)
[2023-04-15 15:17:25.740 267M] Querying gravity database for client fd51:....:e720 (getting groups)
[2023-04-15 15:17:25.740 267M] Gravity database: Client c8:2a:dd:86:f7:71 found. Using groups (2)

But this does not help the actual recognition. The requests are still failing, because the filtering is still performed using the default group.

Debug Token: https://tricorder.pi-hole.net/3lPHmU0f/

[Bucking_Horn]

Can your router be configured to not advertise or offer an IPv6 address as DNS resolver at all?

IPv6 addresses can be tricky to associate with hostnames.

Instead of trying to identify IPv6 addresses, you could also consider to only offer an IPv4 address exclusively for DNS resolution in your local network (see e.g. Hostname resolution and IPv6 - #2 by Bucking_Horn).
Provided your router supports it, that would prompt your dual-stack and IPv4-only clients to send DNS requests only via IPv4, and IPv4 addresses are more easily associated with names.