On Wed, 15 Jul 2026 11:30:52 +0000 Andy Smith <[email protected]> wrote:
> Hi, > > On Wed, Jul 15, 2026 at 12:16:14PM +0100, Joe wrote: > > ;; UDP setup with 2001:500:a8::e#53(2001:500:a8::e) for > > 100.75.195.82.in-addr.arpa. failed: network unreachable. > > […] > > > Maybe a clue: my ISP doesn't yet do IPv6, though I can't see why > > that should affect a DNS enquiry for an IPv4 address. > > You definitely have a problem with IPv6 in that your DNS resolver > machine is trying to communicate with IPv6 addresses while not being > able to. This indicates that the machine thinks it has a global scope > IPv6 address, but it has no IPv6 route. It thinks it SHOULD be able to > use IPv6 but it will always fail. Not up to me, the router apparently has access to IPv6 but doesn't pass it through, though from the menu it looks capable of doing it. But there's no option to enable it, and the ISP (Plusnet, owned by BT) says a trial is under way. But there's no errors in the log with the trace option running, even though something further along is getting network unreachable messages, and the correct data is returned. Without trace the local BIND9 is attempting use of IPv6, which it obviously isn't with trace running. > > You should either fix IPv6 or else remove the IPv6 address - IPv6 will > always be tried first so it's making everything slower for you. I > don't think it is the root of your problem though. I still think > there is some misconfiguration of your bind9 server, as this thing is > resolvable by everyone else. > That's what I hoped, but it is the Debian original setup plus local forward and reverse zones, as I have always done. I used to link it to DHCP to get dynamic updates, but I don't bother these days. I don't make any use of IPv6 in my network, so can I just disable it at the operating system level? At least until Plusnet roll it out to its customers. -- Joe
