Re: [Dnsmasq-discuss] IPV6 preference
further on this: The site that I am trying to nail down to ipv6 only traffic is of course netflix. and it seems like their dns has an extremely low time to live probably so they can keep switching routes to avoid saturating any. Sometimes there are addresses available and sometimes not. It seems that if I 'watch host -t movies.netflix.com' and connect when ipv6 addresses appear I can ensure that I can connect to them over the tunnel. It would be great to override those TTL values and give the ipv6 addresses some persistence. Otherwise one is stuck with the non-selection that netflix offers on this side of the border On Thu, May 9, 2013 at 5:04 AM, /dev/rob0 wrote: >> On Wed, May 8, 2013 at 10:25 AM, /dev/rob0 wrote: >> > On Wed, May 08, 2013 at 05:43:01AM -0700, Ray Klassen wrote: >> >> Is there a way of configuring dnsmasq to always return an >> >> ipv6 address on a DNS request if there are both ipv4 and >> >> ipv6 available? >> > >> > I wouldn't think so. A client either asks for an A record >> > (ipv4) or (ipv6), it does not ask for "an address". >> > > On Wed, May 08, 2013 at 01:58:42PM -0700, Ray Klassen wrote: >> Huh. I would have thought the request by the application would >> be similar to running host. > > An application uses a gethostbyname() call via its system C > libraries.[1] But most applications do not directly query DNS. > host(1) is, of course, an exception. > >> as in >> >> #host google.com >> >> that returns a list of both ipv4 and ipv6 entries... > > The behaviour of host(1) is described in its manual. See the "-t" > option. You are seeing the default behaviour (with no -t query type > specified.) > > > [1] Whilst it might appear that I know what I am talking about, I > confess I really do not. I have no knowledge of the low-level > intricacies of C libraries and their resolver(5) functions. I do, > however, understand the general flow: which software parts do > which things. > -- > http://rob0.nodns4.us/ -- system administration and consulting > Offlist GMX mail is seen only if "/dev/rob0" is in the Subject: > > ___ > Dnsmasq-discuss mailing list > Dnsmasq-discuss@lists.thekelleys.org.uk > http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] IPV6 preference
> On Wed, May 8, 2013 at 10:25 AM, /dev/rob0 wrote: > > On Wed, May 08, 2013 at 05:43:01AM -0700, Ray Klassen wrote: > >> Is there a way of configuring dnsmasq to always return an > >> ipv6 address on a DNS request if there are both ipv4 and > >> ipv6 available? > > > > I wouldn't think so. A client either asks for an A record > > (ipv4) or (ipv6), it does not ask for "an address". > > On Wed, May 08, 2013 at 01:58:42PM -0700, Ray Klassen wrote: > Huh. I would have thought the request by the application would > be similar to running host. An application uses a gethostbyname() call via its system C libraries.[1] But most applications do not directly query DNS. host(1) is, of course, an exception. > as in > > #host google.com > > that returns a list of both ipv4 and ipv6 entries... The behaviour of host(1) is described in its manual. See the "-t" option. You are seeing the default behaviour (with no -t query type specified.) [1] Whilst it might appear that I know what I am talking about, I confess I really do not. I have no knowledge of the low-level intricacies of C libraries and their resolver(5) functions. I do, however, understand the general flow: which software parts do which things. -- http://rob0.nodns4.us/ -- system administration and consulting Offlist GMX mail is seen only if "/dev/rob0" is in the Subject: ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] IPV6 preference
Huh. I would have thought the request by the application would be similar to running host. as in #host google.com that returns a list of both ipv4 and ipv6 entries... On Wed, May 8, 2013 at 10:25 AM, /dev/rob0 wrote: > On Wed, May 08, 2013 at 05:43:01AM -0700, Ray Klassen wrote: >> Is there a way of configuring dnsmasq to always return an ipv6 >> address on a DNS request if there are both ipv4 and ipv6 available? > > I wouldn't think so. A client either asks for an A record (ipv4) or > (ipv6), it does not ask for "an address". > >> I've got an an ipv6 tunnel that, for certain sites, I'd like all >> traffic to be directed to. Problem is (i think) that DNS is round >> robining addresses and sometimes returns an ipv4 address which > > No, as above, the client only gets A if it asks for A. That said, > resolver clients most likely can be configured to prefer ipv6 over > ipv4. See the documentation for your resolver(s). > >> routes traffic away from the tunnel. I suppose I could force this >> using a hosts file, but the addresses for that site are pretty >> dynamic or so I'm given to understand. > > Maybe you want to point to a remote server for those names: > > server=/certain.sites.example/2001:db8::1ce:c01d > -- > http://rob0.nodns4.us/ -- system administration and consulting > Offlist GMX mail is seen only if "/dev/rob0" is in the Subject: > > ___ > Dnsmasq-discuss mailing list > Dnsmasq-discuss@lists.thekelleys.org.uk > http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] IPV6 preference
On Wed, May 08, 2013 at 05:43:01AM -0700, Ray Klassen wrote: > Is there a way of configuring dnsmasq to always return an ipv6 > address on a DNS request if there are both ipv4 and ipv6 available? I wouldn't think so. A client either asks for an A record (ipv4) or (ipv6), it does not ask for "an address". > I've got an an ipv6 tunnel that, for certain sites, I'd like all > traffic to be directed to. Problem is (i think) that DNS is round > robining addresses and sometimes returns an ipv4 address which No, as above, the client only gets A if it asks for A. That said, resolver clients most likely can be configured to prefer ipv6 over ipv4. See the documentation for your resolver(s). > routes traffic away from the tunnel. I suppose I could force this > using a hosts file, but the addresses for that site are pretty > dynamic or so I'm given to understand. Maybe you want to point to a remote server for those names: server=/certain.sites.example/2001:db8::1ce:c01d -- http://rob0.nodns4.us/ -- system administration and consulting Offlist GMX mail is seen only if "/dev/rob0" is in the Subject: ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
