Re: Bug#1063648: krb5: FTBFS on arm64, armel and ppc64el with "Can't resolve hostname" in dh_auto_test

[Chris Hofstaedtler <zeha@debian.org>]

Hi,

On Mon, Feb 12, 2024 at 08:43:07AM -0700, Sam Hartman wrote:
> >>>>> "Simon" == Simon McVittie <smcv@debian.org> writes:
[..]
>     Simon> I am unsure whether there is consensus that "the result of
>     Simon> gethostname() resolves to some address of the local machine"
>     Simon> is also a reasonable thing to demand from all buildds as part
>     Simon> of build-essential: /etc/hosts typically makes this true, but
>     Simon> is not *guaranteed* to do so. On Linux, packages can ensure
>     Simon> that it happens by build-depending on libnss-myhostname
>     Simon> [linux-any], if necessary.

I have asked on #debian-buildd, and got the answer that all buildds
have their own hostname in /etc/hosts. Thus this is not the source
of the problem.

>     Simon> However, even with both of those, if the krb5 test suite (or
>     Simon> protocol) is resolving the local hostname with AF_INET
>     Simon> (IPv4-only), and with either AI_ADDRCONFIG or NULL hints,
>     Simon> then that will not yield any results on an IPv6-only system
>     Simon> for the reasons discussed in #952740 and related bug reports.
> 
> Krb5 is very v6-happy.

It really seems like krb5 is not quite as ipv6-*only*-happy as one
would like to think.

> So, you're suggesting that I fix this by build-depending on
> libnss-myhostname [linux-any] assuming tests are enabled?
> If so, that's easy.

That might or might not help to swipe the problem under a large
enough carpet.

I'll note that on buildds using sbuild with unshare backend, the
setup will look slightly differently. More testing might be
required.

Chris