[SR-Users] Loopback

[Daniel-Constantin Mierla]

Hello,

On 8/28/13 8:22 PM, Marc Soda wrote:
> Thanks, I appreciate it.
>
> In this setup the there are 2 endpoints (700 and 701) peered up to an 
> Asterisk server (172.16.60.6) via a Kamailio proxy (172.16.60.20). 
>  700 (172.16.60.28) is calling 701 (172.16.3.65).  When 701 answers 
> the OK is sent to the proxy and then to Asterisk.  Asterisk is then 
> ACKing the OK.  The ACK is being sent to the proxy and then the proxy 
> should be sending it back to the endpoint.  It is not.  The ACK is 
> being sent to the proxy and then the proxy is sending to itself again, 
> via the loopback interface.  I believe loose_route() should be 
> re-writing the destination to be the endpoint, but it not.
what device is at 701? The 200ok receved from it has the contact address 
with the IP of kamailio:

U 172.16.3.65:5060 -> 172.16.60.20:5060
SIP/2.0 200 OK.
Via: SIP/2.0/UDP 
172.16.60.20;received=172.16.60.20;branch=z9hG4bK9381.d7d662b.0.
Via: SIP/2.0/UDP 172.16.60.6:5060;rport=5060;branch=z9hG4bK0919ead7.
Record-Route: <sip:172.16.60.20;lr;ftag=as5e1a80d8;nat=yes>.
Call-ID: 64a513d30fc6a51e54e8255b7169345c at 172.16.60.6:5060.
From: "Alpha" <sip:700 at 172.16.60.6>;tag=as5e1a80d8.
To: <sip:sip701_tbs at 172.16.60.20>;tag=64c37e7e-19b8-46ae-ad0d-f2a4abe667bc.
CSeq: 102 INVITE.
Allow: PRACK, SUBSCRIBE, NOTIFY, REFER, INVITE, ACK, BYE, CANCEL, 
UPDATE, INFO, REGISTER, OPTIONS, MESSAGE.
*Contact: <sip:sip701_tbs at 172.16.60.20:5060>*.
.....

It should be its IP address, otherwise Kamailio doesn't know where to 
sent requests within dialog.

It seems there is a NAT between your kamailio and 701, as kamailio adds 
alias parameter to Contact in 200ok. That can be used to route the ack, 
like:

handle_ruri_alias();
$ru = $du;
$du = $null;

Do the above for the ACK before calling loose_route(). Then it will get 
out of kamailio, but might not solve the overall routing, if the 701 is 
not at next hop or it doesn't like the r-uri, because it is not what it 
has set.

The best is to ask for the proper fix on 701 device.

Cheers,
Daniel

-- 
Daniel-Constantin Mierla - http://www.asipto.com
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
Kamailio Advanced Trainings - Berlin, Oct 21-24; Miami, Nov 11-13, 2013
   - more details about Kamailio trainings at http://www.asipto.com -

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sip-router.org/pipermail/sr-users/attachments/20130829/7c850e56/attachment.html>