http.client and dns lookups

[Dieter Maurer]

Michael Welle wrote at 2022-2-1 19:28 +0100:
> ...
>That doesn't happen when the 'real' issue occurs. Attaching strace to
>the Python process I can see that resolv.conf is stat'ed and open'ed. I
>guess now I'm more confused than before ;). There must be an additional
>condition that I'm missing.

The DNS service routinely uses caches. Outdated cache values
can cause (apparently non deterministic) failures.