Re: ai_flags in calls to getaddrinfo, broader call for reproducibility check

[Eli Zaretskii <eliz@gnu.org>]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>,  emacs-devel@gnu.org
> Date: Mon, 11 Jan 2021 18:53:51 +0100
> 
> (require 'dns)
> (skip-unless (dns-query "google.com" 'AAAA))
> 
> and then do the network-lookup-address-info tests (although on Windows
> this depends on DNS over TCP working, and either /etc/resolv.conf or a
> working nslookup). Eli?

Tell me what to try, and I will show the results.  TIA.

> > Another perspective on above is that when you mention "behind firewalls up
> > the kazoo", what my intuition imagines is something like: corporate DNS
> > filtering which only allows specific request types and either was never
> > updated to think of AAAA queries as valid, or is operated in a way assuming
> > that users will never have a legitimate need for them (because they "won't
> > be able to use" the results), or does this as a workaround for some broken
> > behavior elsewhere (such as some other device used in the organization
> > which will prefer an IPv6 address response even when it's not reachable,
> > and fail to fall back to IPv4?) or... any number of things like that.
> >
> 
> Iʼd love to be able to persuade Eli's network admins to fix such
> things, but I only attempt things that have a reasonable chance of
> success (and such things are sometimes dependent on vendors rather
> than admins).

No danger of that succeeding in this case, forget it.  I had trouble
convincing them to let me access Git repositories via HTTPS, let alone
SSH.  Every non-standard port under the sun is blocked.  I cannot even
ping any address, have to use tcping instead.

Thanks.