DHCP is handled by LAN router.
When in device in home LAN, DHCP defines internal Technitium DNS as primary DNS. This eases accessing applications by skipping Cloudflare authentication and speeds up DNS resolution.
Currenly home LAN uses IPv4 and router doesn't offer DHCP for IPv6 network. Technitium DNS could also act as a DHCP server but it neither offers DHCPv6. At the moment there is no easy way to distribute local IPv6 nameserver to devices in network.
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