[Dnsmasq-discuss] Need a little IPv6 clarification

[Gui Iribarren]

On Sat, Sep 15, 2012 at 11:20 AM, Gene Czarcinski <gene at czarc.net> wrote:
> On 09/14/2012 03:39 PM, Gene Czarcinski wrote:
>>
>> I have been trying to get some (virtual) IPv6 networks working with
>> dnsmasq acting as both an dhcp6 server and a dns server.  I really do not
>> care how the IP6 addresses are assigned but I do want the system names in
>> dnsmasq's dns service so that these systems can be referred to by name.
>>
>> At some point in time I had dnsmasq actually handing out IP6 addresses via
>> dhcp ... or it certainly looked like that since the address was in the range
>> I specified.  That said, I no longer know just what my configuration was.
>>
>> Basically, I am not sure I understand the meanings or effects of the
>> various parameters on the dhcp-range specification. Specifically, what
>> specifying nothing or ra-name or slaac or ra-stateless or ra-only means ..
>> what are the effects of each are ... or when you combine them what happens.
>>
>> I have read the dnsmasq man page but I need a little more info. It sure
>> would be nice to see what a working configuration looked like.
>>
>> It would be nice if dnsmasq's dns service could be updated regardless of
>> how the address is specified (other than manually) but if only a subset (or
>> even one) will work ... well, that works for me too.
>>
>> Yes, I searched this mailing list and found the messages saying that you
>> had to specify the fqdn and not just the hostname ... but that was well
>> after I did a lot of parameter "testing".
>>
>> My next step is to take a look at the dnsmasq code to see if I can figure
>> things out but a few pointers and hints would be appreciated.
>>
> OK, progress.  I have gotten dnsmasq to do the right thing (I belieive) for
> IPv6 addresses.  However, dns is not updating.  I believe the reason for
> that is that NetworkManager is not sending the FQDN with the dhcp6 request.
>
> But I still have a question.  Reading the man file for dnsmasq I see that
> specifying "ra-names" that dnsmasq should go through this dance to do a dns
> update.  What needs to be specified to get that?

root at host:~# tail -n2 /etc/dnsmasq.conf
enable-ra
dhcp-range=lan, 2001:db8::, ra-names

do note that the ipv6 won't appear in the leases file, but yields

Sep 15 11:19:48 dnsmasq-dhcp[2003]: DHCPREQUEST(br-lan) 10.254.1.56
de:ad:be:ca:fe:ca
Sep 15 11:19:48 dnsmasq-dhcp[2003]: DHCPACK(br-lan) 10.254.1.56
de:ad:be:ca:fe:ca cubito
Sep 15 11:19:48 dnsmasq-dhcp[2003]: RTR-ADVERT(br-lan) 2001:db8::
Sep 15 11:19:48 dnsmasq-dhcp[2003]: SLAAC-CONFIRM(br-lan)
2001:db8:dead:beff:feca:feca cubito

and

root at colmena-gw:~# nslookup cubito
Server:    127.0.0.1
Address 1: 127.0.0.1 localhost

Name:      cubito
Address 1: 2001:db8:dead:beff:feca:feca cubito.domain.net
Address 2: 10.254.1.56 cubito.domain.net

HTH