Reliably detecting the absence of IPv6

[David Härdeman]

December 11, 2025 at 8:41 AM, "Jonas Lochmann" <openwrt at jonaslochmann.de> wrote:
> Am Wed, Dec 10, 2025 at 08:44:00PM -0700, schrieb Philip Prindeville via openwrt-devel:
> 
> > 
> > We had an issue where residential customers on US ISP’s with IPv4 (even if it’s NAT’d) would see a lot of logging from named about not being able to reach IPv6 name servers to resolve AAA records.
> > 
> 
> Are you talking about A or AAAA records?

I'm guessing it's rather about being unable to reach nameservers via IPv6...and not any specific kind of record.

> > 
> > The workaround is to run bind with ‘-4’ to eliminate this.
> > 

Why not remove the log messages instead?

Haven't tested it (and haven't seen the exact log messages you're seeing), but something like this:

logging {
   category lame-servers { null; };
};