Re: After enabling IPv6 curl github.com fails, succeeds with IPv4

[Christof Meerwald <cmeerw%cmeerw.org@localhost>]

On Tue, Jul 21, 2026 at 08:50:45PM +0200, Martin Husemann wrote:
> On Wed, Jul 22, 2026 at 12:04:33AM +0530, Mayuresh wrote:
> > That implicit suffixing is seen happening in tcpdump for other domain
> > names, too, when the given name fails to find AAAA record.
> > 
> > It's .in, possibly because my hostname ends in that.
> 
> No, that is no good reason for it.
> There must be a "domain" or "search" entry in /etc/resolv.conf.

I am actually seeing a similar thing that I don't have either "domain"
or "search" in /etc/resolv.conf, but the resolver is trying to use the
domain name from my hostname to search (if the initial query failed).
And if I don't have a fqdn hostname, then the resolver just tries the
same query again.

I think the code responsible for this is in:

https://nxr.netbsd.org/xref/src/lib/libc/resolv/res_init.c#531


Christof

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