Re: Should a nameserver know about itself?

[Bill Woodcock <woody@zocalo.net>]

      On Wed, 9 May 2001, Randy Bush wrote:

    > > Is the assumption that a nameserver should have information about itself
    > > correct?
    > no.  
    > analogy: i have phone directories in my house, but i happen not to have one
    > for the town in which my house is situated.

So, as an ignorant layer-2/layer-3 person stretching to understand
this layer-5 DNS stuff, lemme see if I can render that as an example
rather than an analogy:

APNIC delegates 2.0.0.0/16 to Foo-ISP:

    $ORIGIN 2.in-addr.arpa.
    0 IN SOA 0.2.in-addr.arpa root.apnic.net n n n n n
    IN NS ns.apnic.net.
    $ORIGIN 0.2.in-addr.arpa.
    0 IN NS ns2.foo-isp.net.

ns2.foo-isp.net has a zone file for 0.0.2.in-addr.arpa:

    $ORIGIN 0.2.in-addr.arpa.
    0 IN SOA 0.0.2.in-addr.arpa root.foo-isp.net n n n n n
      IN NS ns2.foo-isp.net.
    $ORIGIN 0.0.2.in-addr.arpa.
    0 IN PTR host0.foo-isp.net.
    1 IN PTR host1.foo-isp.net.
    254 IN PTR host254.foo-isp.net.
    255 IN PTR host255.foo-isp.net.

However, ns2.foo-isp.net's IP address is 1.0.2.1, and it isn't
authoritative for either the 2.0.1.in-addr.arpa. zone or the
foo-isp.net. zone, those are both held by ns1.foo-isp.net, whose IP
address is 1.0.1.1:

    $ORIGIN net.
    foo-isp IN SOA foo-isp.net root.foo-isp.net n n n n n
            IN NS ns1.foo-isp.net.
    $ORIGIN foo-isp.net.
    ns1 IN A 1.0.1.1
    ns2 IN A 1.0.2.1

    $ORIGIN 0.1.in-addr.arpa.
    1 IN SOA 1.0.1.in-addr.arpa root.foo-isp.net n n n n n
      IN NS ns1.foo-isp.net.
    2 IN SOA 2.0.1.in-addr.arpa root.foo-isp.net n n n n n
      IN NS ns1.foo-isp.net.
    $ORIGIN 1.0.1.in-addr.arpa.
    1 IN PTR ns1.foo-isp.net.
    $ORIGIN 2.0.1.in-addr.arpa.
    1 IN PTR ns2.foo-isp.net.

So ns1.foo-isp.net would know about itself, but ns2.foo-isp.net
would not know anything at all about itself beyond the fact that
"ns2.foo-isp.net" was the data of an NS record in its zone file.
Both would be properly configured.

Is that right?

                                -Bill