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Reverse DNS entries for IPv6 addresses are not working. Everything I've read on the subject says the following configuration should work:

In named.conf:

zone "" IN {
      type master;
      file "/var/lib/bind/ipv6reverse.hosts";
      allow-update { none; };

In /var/lib/bind/ipv6reverse.hosts:

$TTL 2d
@       IN      SOA     ns1.domain.ca.  hostmaster.domain.ca. (
            2011051104 ; serial
            1h      ; refresh
            1h      ; retry
            20d     ; expire
            2d      ; minimum
    IN      NS      ns1.domain.ca.
    IN      NS      ns2.domain.ca.                IN      PTR     smtp.domain.ca.

When I try to do the reverse hostname lookup, I get the following error:

# host -6 2605:7c00:3::23 2605:7c00:3::11
Using domain server:
Address: ::ffff:

Host not found: 3(NXDOMAIN)

As far as I can tell, this should be found.

The syslog for bind has some rather cryptic entries that may be related:

May 12 10:28:57 www3 named[16018]:   validating @0xb253cf10: . SOA: no valid signature found
May 12 10:28:57 www3 named[16018]:   validating @0xb253cf10: . NSEC: no valid signature found
May 12 10:28:57 www3 named[16018]:   validating @0xb253cf10: org NSEC: no valid signature found
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1 Answer 1

up vote 3 down vote accepted

Oh Grr! There was a . at the end of I swear I tried this 6 times over. Stupid syntax errors.

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Snigger. IPv6 rDNS is a pain, isn't it. I'm getting used to the look, but it's UGLY! Since we can't subnet below a /64, why not have all the last 16 characters as one block rather than having to count dots? –  Richard Gadsden May 14 '11 at 14:19
Alternatively, we should all consider generating IPv6 rDNS programatically,e.g. using something like member.wide.ad.jp/~fujiwara/v6rev.html - this is much less error-prone than writing it out by hand. –  David North May 28 '11 at 9:44
Strange that I couldn't find that in Google. :) It wasn't from lack of trying either. –  Ernie May 31 '11 at 21:17

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