PTR records for v6 hosts

Doug Barton dougb at dougbarton.us
Mon Aug 31 19:26:50 CEST 2009


Ron Broersma wrote:
> 
> On Aug 30, 2009, at 8:42 AM, Seth Mattinen wrote:
> 
>> I'm curious as to how everyone is doing PTR records in DNS for their v6
>> hosts. Are you just letting autoconf hosts go without? Do you manually
>> create one once you know what it's autoconf address will be? Or do you
>> use DHCP with a predefined pool that's easy to create a PTR range for?
> 
> We wrote a tool that regularly polls the routers, grabs the ARP and ND
> tables (using appropriate snmp MIBs), looks for all the global unicast
> IPv6 addresses in the list, and then using their MAC address we map to
> the associated IPv4 address, then use that to look up the IPv4 PTR
> record in DNS, then use that to build an IPv6 PTR record and use dynamic
> DNS update to update the zone (with various optimizations such as
> caching, garbage collection, etc). 

Have you considered open-sourcing such a tool? I'm sure that a lot of
people would find it very valuable.


> That works well for us (dealing
> with thousands of v6 hosts on our net), although there are challenges
> with differences in how each vendor implements the v6 MIBs, and churn
> from those horrible privacy/temporary addresses [RFCs 3041, 4941] that
> that all Microsoft OS's enable by default). 

Personally I like my privacy, but I can see how it would be difficult
to deal with. :)


Doug


More information about the ipv6-ops mailing list