Do not announce upstream DNS server via DHCP

Installing and Using OpenWrt
1

Hi,

I want OpenWRT to only announce itself as DNS server but it also announces the (IPv6) DNS server from my provider. The issue is that Linux clients, under certain circumstances, revert the resolution order and use the provider DNS server, which obviously doesn’t know my local domain.

I simply want OpenWRT to announce itself only (for IPv4 and/or v6) as DNS server via DHCP.

I went through IPv6 config to advertise local DNS server - #2 by lleachii but my dialog doesn’t show “Announced IPv6 DNS servers“ which is also documented in the Wiki https://openwrt.org/docs/guide-user/base-system/dhcp_configuration#providing_custom_dns_with_dhcp.

As a side note, it’s not exactly what I want because I don’t want to enter myself the address(es), which might change, I want OpenWRT to be smart enough to announce just itself.

2

Do not enable dhcp6 passthrough?

3

Don’t I then lose the IPv6 capability alltogether?

4

No idea, you changed default parameter as if knowing better.
Bow you get what your provider gives.

1 Like
5

That was not exactly helpful.

6

That are the default settings.

3 Likes
7

I’m carrying this configuration since quite a while, I don’t deny that I might have changed the default at some point in time but I must admit that I can’t remember.

My config looks today like this:

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Can the issue be that WAN6 is designated master?

1 Like
8

Relay mode then all bets are off

Relay mode is hopeless get a real ISP which will delegate a proper Prefix

2 Likes
9

You can redirect DNS requests to your server/router https://openwrt.org/docs/guide-user/firewall/fw3_configurations/intercept_dns
But first check IPv6 addresses assigned to wan6 interface, if it is IPv6-PD with mask of /64 or less you do not need to relay dhcpv6

1 Like