Question about "Bogus LOOPBACK" message

[O'Neil,Kevin]

I think the bottom line is that you can ignore the message since the problem
is a misconfiguration on the other name server.

In case you are not aware of it, there's a web page with explanations of
most of BIND's messages: http://www.acmebw.com/askmrdns/bind-messages.html.


Here's an example I've found that illustrates the situation with the dig
output and the resulting log messages:

/home/oneil 11:30am: dig -x 209.119.4.196

; <<>> DiG 8.3 <<>> -x 
;; res options: init recurs defnam dnsrch
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0
;; QUERY SECTION:
;;      196.4.119.209.in-addr.arpa, type = ANY, class = IN

;; ANSWER SECTION:
196.4.119.209.in-addr.arpa.  1D IN PTR  timmy-196.ksni.net.

;; AUTHORITY SECTION:
4.119.209.in-addr.arpa.  1D IN NS  localhost.

;; Total query time: 5115 msec
;; FROM: net-thing to SERVER: default -- 132.174.47.100
;; WHEN: Fri Dec  7 11:30:45 2001
;; MSG SIZE  sent: 44  rcvd: 99

/home/oneil 11:30am: tail /etc/named/log.msgs
07-Dec-2001 11:30:40.606 default: info: ns_forw:
query(196.4.119.209.in-addr.arpa) Bogus LOOPBACK A RR (localhost:127.0.0.1)
learnt (A=localhost:NS=207.239.115.20)
07-Dec-2001 11:30:40.607 default: info: sysquery: findns error (NXDOMAIN) on
localhost?
07-Dec-2001 11:30:40.651 default: info: ns_resp:
query(196.4.119.209.in-addr.arpa) Bogus LOOPBACK A RR (localhost:127.0.0.1)
learnt (A=localhost:NS=207.239.115.20)
07-Dec-2001 11:30:40.652 default: info: sysquery: findns error (NXDOMAIN) on
localhost?

...Kevin O'Neil


-----Original Message-----
From: Kevin Darcy [mailto:kcd at daimlerchrysler.com]
Sent: Thursday, December 06, 2001 5:41 PM
To: bind-users at isc.org
Subject: Re: Question about "Bogus LOOPBACK" message



My guess is that some nameserver gave you a referral to a nameserver that
resolves to 127.0.0.1. This is obviously bogus. Since you have obscured the
actual domain names involved, it's impossible to tell why you may have
received
such a referral, or what you might be able to do about it.


- Kevin

Takahiro Sato wrote:

> Hello,
>
> I am in trouble with DNS log message(syslog) of internal DNS,
>
> "sysquery : query(SOME-DOMAIN-NAME) Bogus LOOPBACK A RR
(localhost:127.0.0.1)
>  learn (A=localhost:NS=A.B.C.D)"
>
> (*) A.B.C.D is External DNS server address.
>
> If anyone have any idea, please teach me about this.
>
> Thanks!
>
> This illustrates my DNS server environment.
>
>                   THE INTERNET
>                  /             \
>                 /               \
>                /                 \
>  |---------------|  forward    |---------------|
>  | Internal DNS  |------------>| External DNS  |
>  | (foo.prv)     |  root NS    |  (bar.xyz)    |
>  |               |------------>|               |
>  |---------------|             |---------------|
>         |
>         | private network
>         |
>     ---------
>     |Client |
>     ---------
>
> Internal DNS
>    Multi-homed DNS(it is connected to private network
>    and INTERNET).  It is authority of foo.prv that is
>    private network zone. Query of the name other than
>    "foo.prv" is forwarded to external DNS. If its
>    forwarded (recursive) query is not answered, then
>    internal DNS sends (non-recursive) query to external
>    DNS(as root nameserver).
>
> External DNS
>    This nameserver is authority of "bar.xyz.". It's
>    connected to INTERNET.
>
> Internal DNS configuration like this,
>
>   options {
>           forwarders {
>                   A.B.C.D;   // it's External DNS's IP Address;
>           };
>   };
>
>   zone "foo.bar" in {
>           type master;
>           file "db.foo.bar"; // private network
>   };
>
>   zone "10.in-addr.arpa" in {
>           type master;
>           file "db.10";
>   };
>
>   zone "." in {
>           type hint;
>           file "root.cache"; // In "root.cache", External DNS
>                       // is specified as ROOT nameserver.
>   };
>
> ---
> E-mail : t_sato at rbec.co.jp