Re: Any way to bypass nameserver call in IPV6 ???

From: T.R.Bennett (bennett.tony_at_cnf.com)
Date: 08/31/04 

Date: 31 Aug 2004 08:40:18 -0700

lathamr@us.ibm.com (Richard D. Latham) wrote in message news:<acwg5k3r.fsf@us.ibm.com>...
> bennett.tony@cnf.com (T.R.Bennett) writes:
>
> > Apache and several other open source projects have converted
> > their code from using gethostbyname() to using getaddrinfo().
> >
> > They call getaddrinfo with a hints.ai_family = AF_UNSPEC,
> > which means "get me both IPV4 as well as IPV6" addresses.
> >
> > If I were using gethostbyname(), then I could prevent going
> > to the nameserver if I have the host in the /etc/hosts file
> > and had /etc/netsvc.conf contain "hosts= local,bind".
> >
>
> No, you need to enter "hosts=local=auth,bind" to inform the resolver
> logic that the local hosts file is authoratitive, else it will keep
> checking sources in the chain until either it's asked everybody, or
> someone has given an authoratitive answer.
>
> There's also an env var you can set to get this behavior, but I can't
> remember what it is right now.
>
>
> > How do I create the same behaviour for IPV6 addresses ?
> >
> > Additionally, I noted that even though I specify a FQDN in
> > the getaddrinfo() call, it tries both that name as well as
> > a name created by appending my domain name. For example:
> > - I specify XXX.YYY.COM
> > - getaddrinfo does IPV6 queries for:
> > XXX.YYY.COM
> > XXX.YYY.COM.YYY.COM
> > Is this correct behaviour???
> >
> > Thanks,
> > -tony
>
> Sorry, I'm on airplane just now and can't check, but IIRC , you need
> to terminate the request string with a period '.', to prevent the
> resolver logic from trying all the domains you have specified in the
> /etc/"blah blah blah" file.

Richard,

    I've tried the following netsvc.conf definitions with the corresponding
results:
      
  With resolv.conf containing only domain and nameserver lines:

      netsvc.conf Format Nameserver Queries
      hosts=local=auth,bind AAAA XXX.YYY.COM
                                    AAAA XXX.YYY.COM.YYY.COM
      hosts=local=auth,bind4 - No QUERY -

  It appears the problem has been solved.

  Thanks goes out to Richard Latham and Dale Talcott.

-tony

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