Re: [gentoo-user] Managing rDNS with BIND

[Alan McKinnon <alan.mckinnon@gmail.com>]

On Sat, 14 Jan 2012 13:35:16 -0600
Carlos Sura <carlos.sura1@googlemail.com> wrote:

> On 8 January 2012 16:02, Alan McKinnon <alan.mckinnon@gmail.com>
> wrote:
> 
> > On Sat, 7 Jan 2012 09:45:44 -0600
> > Carlos Sura <carlos.sura1@googlemail.com> wrote:
> >
> > > Hello mates,
> > >
> > > I have a problem, my provider does not want to set rDNS to my IP's
> > > since I have 5 IP's rotating for my server, I don't know why. So
> > > he told me I can do this manually.
> > >
> > > So I've added this as a master zone:
> > > $ttl 38400
> > > 80.236.109.in-addr.arpa. IN SOA dominio.dominio.com.
> > > abuse.dominio.com. (notice that last digits are miss)
> > > 1325905990
> > > 10800
> > > 3600
> > > 604800
> > > 38400 )
> > > 80.236.109.in-addr.arpa. IN NS dominio.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR mail.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR ns1.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR mail.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR ns2.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR mail.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR mail.dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR dominio.com.
> > > xx.xx.xxx.xxx.in-addr.arpa. IN PTR mail.dominio.com.
> > >
> > >
> > > But it does not reflect any change in any machine, just in the
> > > local machine I get the answer, when I try in any other machine,
> > > it still showing me the rDNS of my provider.
> >
> >
> > The reason is quite simple and most sane ISPs will do it that way.
> >
> > rDNS is NOT your A records in reverse, and you have no right of
> > access to the zone.
> >
> > in-addr.arpa serves an entirely different purpose, it documents the
> > layout of the ISPs address space. Your 5 IPs have not been
> > delegated to you and you do not own them per whois, they still
> > belong to your ISP and are merely recorded in the ISP record as
> > assigned for your use.
> >
> > Therefore the ISP will use their own documentation standards to
> > determine what is in the rDNS zone.
> >
> > Additionally, delegating out a /29 is a gigantic pain in the arse
> > and leads to an unmaintainable mess in very short order (so says
> > the poor sucker that's had to fix it...). At work we never
> > sub-delegate out rDNS to customers; but we do do it for downstream
> > re-sellers as they are ISPs in the in own right.
> >
> > So your ISP is quite correct in what they are saying. However, I
> > would like to see a clarification of what your support contact
> > means when he says "do it manually" - that doesn't make any sense
> >
> > --
> > Alan McKinnon
> >
> >
> 
> Hello Alan McKinnon,
> 
> Thank you for your answer, I get you now you explained everything I
> needed to know. About my ISP, they changed it for me, since I was
> sending a lot of ticket support to them, because they have a poor
> support, I understand they don't manage and help me with a lot of
> things, basically I don't need them, the only thing I was asking for
> is to set the rDNS for me, hopefully they did, cause I told them,
> that I really don't understand what they mean by "do it by myself"
> and I was reading all BIND ebook to understad how delegation works.
> 
> Regards
> 

Hi Carlos,

I'm glad to hear you came right.

Yes, having your ISP update their rDNS with your machine's name is the
best solution all round.


-- 
Alan McKinnnon
alan.mckinnon@gmail.com