On 3/26/2013 5:33 PM, Daniel-Constantin Mierla wrote:
Hello,
On 3/25/13 9:23 AM, Miguel Baptista
wrote:
Hello,
I have been doing some tests with kamailio and IPv6.
My initial setup was IPv6 only and now am I extending it to a
dual-stack environment. Well, and now I am starting to face some
(interesting) challenges.
So, the first step in the dual-stack environment was to install
RTP Proxy and configured kamailio to use it. With this setup,
the UAs locally registered were able to communicate with
each-other no matter with address family (IPv4/IPv6) they were
using. So far so good.
But now I want to extend my tests a bit more ... I want to
communicate with the "outside world" (using ENUM and domain
based SIP URIs). Do I have a way to know if the "destination" is
IPv4 or IPv6? Because I need that information in order to
properly bridge the calls on rtpproxy.
I tried to use the onsend_route but it didn't work. I mean, I am
able to know if the "next-hop" is IPv6 or IPv4 but it seems that
it is "too late" to use rtpproxy. BTW ... I am assuming that if
the "next-hop" is IPv6 then the final user agent will also be
IPv6 (the same for IPv4)
Should I use some other approach? For example, failure route
instead?
Does anyone have a similiar setup? How are you solving this
issue?
I see few options here:
- use two outbound proxies, one for IPv4 and one for IPv6 -- from
your main proxy you can do parallel forking to the two edge
proxies, one of the branches will fail if no device/server is
listening on that protocol (or it will be dropped in onsend_route
if after dns is not the expected IP version)
- use lua or other embedded language to do dns lookup from config
and decide in branch route what to do. Alternative is to execute
external script or some web service
- export to the config the internal dns lookup function so it will
be done on demand and detect outgoing IP layer version (this
requires c coding, perhaps not much -- preferable solution,
because will remove it from my to-do)