repeated records causse "CNAME and OTHER" error in 8.2x

[Mark Ivens]

Hi,

I've come across the following problem today after upgrading from 8.1.2 to
8.2.1. Since 8.2 and above treat a CNAME and OTHER error as a hard error.
Consider the following zone file where someone
[me :)] has erroneously repeated an MX and CNAME record:

localhost# less /etc/namedb/foobar.co.uk.zone
$TTL                            172800
@       IN      SOA     localhost.noc.clara.net.  mivens.clara.net. (
                                1999062225      ; Serial number
                                172800          ; Refresh every two days
                                3600            ; Retry every hour
                                1728000         ; Expire every 20 days
                                172800 )        ; Minimum 2 days


                IN      NS      localhost.noc.clara.net.
                IN      NS      localhost.noc.clara.net.

foo             IN      MX      10 foo.clara.net.
ftp.foo         IN      CNAME   bar.clara.net.

;;;; [snip]
;;;; [snip]
;;;; [snip]

foo             IN      MX      10 foo.clara.net.
ftp.foo         IN      CNAME   bar.clara.net.

Bind 8.2.1 rejects the above zone file:

Jun 22 20:01:17 localhost named[21182]: starting.  named 8.2.1 Tue Jun 22
14:12:58 BST 1999 
mark at localhost.noc.clara.net:/usr/local/src/bind/src/bin/named
Jun 22 20:01:17 localhost named[21182]: limit files set to fdlimit (1024)
Jun 22 20:01:17 localhost named[21182]:
foobar.co.uk.zone:21:ftp.foo.foobar.co.uk: CNAME and OTHER data error
Jun 22 20:01:17 localhost named[21182]: master zone "foobar.co.uk" (IN)
rejected due to errors (serial 1999062225)
Jun 22 20:01:17 localhost named[21183]: Ready to answer queries.

Nowhere else were any records for foo.foobar.co.uk (or foobar.co.uk itself 
for that matter)efined and the only other zone file in
named.conf was for the 127.0.0 reverse lookups:

localhost# less /etc/named.conf 
options {
        directory "/etc/namedb";
        query-source address * port 53;
};
zone "." {
        type hint;
        file "named.root";
};

zone "0.0.127.IN-ADDR.ARPA" {
        type master;
        file "localhost.rev";
};
zone "foobar.co.uk" {
        type master;
        file "foobar.co.uk.zone";
};


I would have thought with that the problem with the above zone file does not
constitute a CNAME and OTHER data error. My interpretation would be that only
if, for example, there was an MX or an A record subsequently defined for
ftp.foo in the example above should the "CNAME and OTHER" error be generated.  
Shouldn't bind only be giving a warning about a repeated record and then
accept the above zone file?

It's far too easy with a large zone file to make a mistake and duplicate a
couple of records. If that results in bind 8.2.1 rejecting the zone file for
a large domain then I would have thought that pretty dangerous.

I was wondering whether others feel this behaviour is incorrect or
whether my interpretation is wrong.

I also haven't seen an easy way of stopping bind 8.2x treating "CNAME and
OTHER" errors as soft errors (apart from going back to 8.1.2, of course).

--
********************************************************************
                     Mark Ivens   mivens at clara.net
                            ClaraNET  Ltd
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