[Kamailio-Users] DNS lookup for requests within dialog

[catalina oancea]

As I said earlier, I misunderstood some things. sorry for the trouble.


2009/9/25 Olle E. Johansson <oej at edvina.net>:
>
> 24 sep 2009 kl. 12.46 skrev Daniel-Constantin Mierla:
>
>> Hello,
>>
>> On 24.09.2009 12:10 Uhr, catalina oancea wrote:
>>>
>>> Hi,
>>>
>>> In my scenario kamailio is not a registrar, it's just a proxy
>>> forwarding requests from asterisk to the provider.
>>>
>> I see.
>>
>> As Juha said, REGISTER does not create a real dialog, since the contact in
>> 200OK is the address of publisher not of destination. So a proxy does not
>> have within-dialog like routing information.
>>
>> So here is a hack you can try:
>> - add record route on your proxy
>> - the provider should add its own record route to REGISTER reply -- if it
>> is kamailio, that is simple via append_to_reply() from textops, just before
>> save() call.
>> - hope/pray that asterisk is using these dialog info for building
>> re-registration messages
>> - on your kamailio route based on Route header
>>
> RFC 3261, section 10.3:
> Registrars MUST ignore the Record-Route header field if it is included in a
> REGISTER request. Registrars
> MUST NOT include a Record-Route header field in any response to a REGISTER
> request.
> A registrar might receive a request that traversed a proxy which treats
> REGISTER as an unknown request and
> which added a Record-Route header field value.
>
> Oops.
>
> /O
>>
>> Cheers,
>> Daniel
>>
>>>
>>> 2009/9/24 Daniel-Constantin Mierla <miconda at gmail.com>:
>>>
>>>> Hello,
>>>>
>>>> On 24.09.2009 11:47 Uhr, catalina oancea wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>>
>>>>> I tested the following scenario:
>>>>>
>>>>> astreisk                        kamailio
>>>>>  provider(hostname)
>>>>>      -------------------->    dns lookup     -------------------->
>>>>>        REGISTER 1                              REGISTER 1
>>>>>
>>>>>       <--------------------                      <--------------------
>>>>>        401                                          401
>>>>>
>>>>>        -------------------->   dns lookup     -------------------->
>>>>>        REGISTER 2                              REGISTER 2
>>>>>        (same dialog, increased cseq)
>>>>>
>>>>>
>>>>>
>>>>> It seems that kamailio does dns lookup again when receiving REGISTER
>>>>> 2, although both registers are part of the same dialog. Is this the
>>>>> expected behavior?
>>>>>
>>>>>
>>>>>
>>>> IIRC now, there is no place in registrar related modules (registrar and
>>>> usrloc) where DNS query is done. You have some checks in your config
>>>> that
>>>> caused that.
>>>>
>>>> There is also an option to fetch existing contacts from location and see
>>>> if
>>>> it is an update (matching by call id and cseq) and do directly
>>>> save("location").
>>>>
>>>> Cheers,
>>>> Daniel
>>>>
>>>> --
>>>> Daniel-Constantin Mierla
>>>> * Kamailio SIP Masterclass, Nov 9-13, 2009, Berlin
>>>> * http://www.asipto.com/index.php/sip-router-masterclass/
>>>>
>>>>
>>>>
>>>
>>> _______________________________________________
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>>> Users at lists.kamailio.org
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>>> http://lists.openser-project.org/cgi-bin/mailman/listinfo/users
>>>
>>>
>>
>> --
>> Daniel-Constantin Mierla
>> * Kamailio SIP Masterclass, Nov 9-13, 2009, Berlin
>> * http://www.asipto.com/index.php/sip-router-masterclass/
>>
>>
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>> Users at lists.kamailio.org
>> http://lists.kamailio.org/cgi-bin/mailman/listinfo/users
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>
> ---
> * Olle E Johansson - oej at edvina.net
> * Cell phone +46 70 593 68 51, Office +46 8 96 40 20, Sweden
>
>
>
>