[OpenSIPS-Users] $(avp(attr)[$T_branch_idx]) is NULL for second INVITE. How to solve it ?

Liviu Chircu liviu at opensips.org
Tue Aug 29 11:34:49 EDT 2017


Hi Rodrigo,


Just trying to understand the flow here - could it be actually a 
Re-INVITE that goes through your sequential routing block, thus lookup() 
is not called, leaving $avp(attr) NULL throughout that transaction?


Regardless of the above, in OpenSIPS terms, each "branch" points to a 
different destination. In our case, we're talking about a retry, not a 
serial/parallel forked call. Which means that you should only bother 
with $T_branch_idx if a lookup() could yield more than one device to be 
contacted for the same AoR.


Best regards,

Liviu Chircu
OpenSIPS Developer
http://www.opensips-solutions.com

On 29.08.2017 18:05, Rodrigo Pimenta Carvalho wrote:
>
>
> Dear SIPusers,
>
>
> In my project I use to keep a valuable information in table location. 
> This is about the state of a subscriber's localization.
>
> I have to read such information for the callees, every time a new 
> branch is created and every time a INVITE is answered with SIP OK.
>
> So, my OpenSIPS configuration has something similar to the following code:
>
>
> 1    route{
>
> 2           ...  // hidden code for simplification.
>
> 3 lookup("location","m")
>
> 4           ...
>
> 5     route(relay);
>
> 6    }
>
>
> 7    route[relay]{
>
> 8       if (is_method("INVITE")) {
> 9                ...
> 10 t_on_branch("per_branch_ops");
> 11 t_on_reply("handle_nat");
> 12 t_on_failure("missed_call");
> 13     }
> 14     ...
>
> 15  }
>
>
> 16    branch_route[per_branch_ops] {
> 17        ....
>
> 18        $(avp(attr)[$T_branch_idx])
>
> 19        ...
>
> 20    }
>
>
> 21    onreply_route[handle_nat] {
>
> 22        ...
>
> 23 $(avp(attr)[$T_branch_idx])
>
> 24        ...
>
> 25    }
>
> 26    ...
>
>
> In a determined call, when the OpenSIPS receives the INVITE and then a 
> SIP OK (200), the code gets right value in lines 18 and 23.
>
> In such call, the SIP OK (from callee) offers a kind of video that the 
> caller can't support. In this case the caller sends another SIP INVITE 
> with inactive video (SDP).
>
> In this moment, OpenSIPS gets this second INVITE and create a new branch.
>
> However, for this new branch, lines 18 and 23 give me NULL for 
> $(avp(attr)[$T_branch_idx]).
>
>
> How to solve this issue?
>
>
> Any hint will be very helpful!!
>
>
> Best regards!
>
>
> P.S.: I'm not expert in SIP.
>
>
> RODRIGO PIMENTA CARVALHO
> Inatel Competence Center
> Software
> Ph: +55 35 3471 9200 RAMAL 979
>
>
> _______________________________________________
> Users mailing list
> Users at lists.opensips.org
> http://lists.opensips.org/cgi-bin/mailman/listinfo/users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensips.org/pipermail/users/attachments/20170829/f0e2190c/attachment.html>


More information about the Users mailing list