Magnus Hagander <magnus@hagander.net> writes:
> On Wed, Jun 30, 2021 at 9:20 PM Bruce Momjian <bruce@momjian.us> wrote:
>> Oh, I used the -4 option and my failures stopped. Glad this thread was
>> helpful for you too. I never expected IPv6 to lead to failures, just
>> possible delays, but I have now learned, at least with DNS, it can cause
> It shouldn't.
> I regularly work from networks with no native ipv6 and these things
> work perfectly fine.
IME, things work just well enough that it takes awhile to realize that
they aren't entirely okay. It took me a few months after upgrading to
RHEL8 to make the connection between occasional (maybe one-in-a-thousand)
mail failures and not having bind set up with "-4". I don't know whether
the previous setup avoided that because older bind defaulted differently
or because there was some change in kernel configuration.
regards, tom lane
