[SR-Users] dispatcher problem

[Klaus Feichtinger]

 Carsten,

thanks for your clarification. I guessed that it was influenced by the
retransmission of the OPTIONS request. But I hoped this "check-health"
mechanism would not be based on the standard mechanism. Because with
this behaviour I do not understand what the former default interval of
10 seconds should bring? The default timeout for the request is 30
seconds and the check-health interval is 10 seconds. So in every
"period" the server has to handle 3 requests to one and the same target
in parallel....... This does - from my point of view - not make sense.

Therefore I have set the ping_interval to a value of 60 seconds and can
now live with the retransmission (without interference).

regards

Klaus
> Hi,
>
> what you are seeing here, are the retransmits for the OPTIONS-Requests.
> The Dispatcher checks every 10 seconds for "dead" destinations and
> then sends out the OTIONS-Request using TM (which is doing the
> retransmits).
>
> This might be a little overlapping, e.g.
> - OPTIONS-Request (initial request, 1st try)
> - 0,5s (retransmit, 1st try)
> - 1s (retransmit, 1st try)
> - 2s (retransmit, 1st try) = 3,5 Seconds from initial request
> - 4s (retransmit, 1st try) = 7,5 Seconds from initial request
> - 10s OPTIONS-Request (initial request, 2nd try)
> - 10,5s (retransmit, 2nd try)
> - 11,5s (2x, retransmit, 2nd try + retransmit, 1st try)
> - 13,5s (retransmit, 2nd try)
> - 15,5s (retransmit, 1st try)
> (and so on).
>
> That is the reason for this behaviour, and may look confusing....
>
> Carsten
>
> 2010/9/10  <klaus.lists at inode.at>:
>> Hello Daniel,
>>
>> these days I'm playing a lot with the dispatcher module and from my point
>> of view I found a strange behaviour of the module, which is not according
>> the description in the documentation and as you've explained in the list.
>>
>> I've learned that polling of failed gwys is only supported when the
>> parameter "ds_ping_interval" is set to a value above '0' (the default
>> value of '10' is no longer supported).
>>
>> However, when a gateway is in probing state the polling interval is never
>> the value that is set in the modparam, it is - in dependent from this
>> value - always a 'fix' period. E.g. the OPTIONS message is sent in
>> following interval: 0.5-1-2-4-4-4-4 and afterwards it looks a little bit
>> chaotic without a specified interval (= random).
>>
>> Is this as expected or do I miss another modparam that is mandatory? My
>> config looks as follows:
>> # ----- DISPATCHER -----
>> modparam("dispatcher", "db_url",
>> "mysql://openser:openserrw@localhost/openser")
>> modparam("dispatcher", "table_name", "dispatcher")
>> modparam("dispatcher", "dst_avp", "$avp(AVP_DST)")
>> modparam("dispatcher", "grp_avp", "$avp(AVP_GRP)")
>> modparam("dispatcher", "cnt_avp", "$avp(AVP_CNT)")
>> modparam("dispatcher", "ds_ping_from", "sip:proxy at 192.168.37.87")
>> modparam("dispatcher", "ds_probing_mode", 0)
>> modparam("dispatcher", "ds_ping_interval", 20)
>> modparam("dispatcher", "flags", 2)
>> modparam("dispatcher", "force_dst", 1)
>>
>> regards,
>>
>> Klaus Feichtinger
>>
>>
>>>   Hello,
>>>
>>> I fixed, thanks for pointing out.
>>>
>>> We would need a documentation marshall that should update the docs as
>>> something related is discussed on the lists. But none really volunteered
>>>  to do it. For developers is not always obvious or easy (due to lack of
>>> time) to track the doc changes.
>>>
>>> Anyone stepping forward?
>>>
>>> Cheers,
>>> Daniel
>>>
>>> On 9/8/10 12:01 PM, klaus.lists at inode.at wrote:
>>>> Klaus, Daniel-Constantin,
>>>>
>>>> I had the same "problem" and found the 'solution' in archived mails
>>>> from diverse mailing lists only.
>>>>
>>>> In general the documentation is not really up-to-date. Because also
>>>> the hint in modules documentation, chapter 3.16 "[...] if compiled
>>>> with the probing of failed gateways enabled [...]" is no longer valid
>>>> (as commented by Daniel-Constantin in another list).
>>>>
>>>> Please update the documentation for the next major release 3.1 to
>>>> avoid any more confusions.
>>>>
>>>> THX
>>>>
>>>> regards,
>>>> Klaus
>>>>
>>>>> Am 07.09.2010 20:58, schrieb Daniel-Constantin Mierla:
>>>>>> Hello,
>>>>>>
>>>>>> you have to set the ping interval parameter:
>>>>>> http://kamailio.org/docs/modules/stable/modules_k/dispatcher.html#id2590104
>>>>>>
>>>>>> I see that documentation says its default value is 10, but in
>>>>>> sources is 0, which means this feature is disabled.
>>>>> That was the reason I didn't configured it.
>>>>>
>>>>> Thanks
>>>>> Klaus
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing
>>>>> list sr-users at lists.sip-router.org
>>>>> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>>>>
>>>>
>>>> _______________________________________________
>>>> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing
>>>> list sr-users at lists.sip-router.org
>>>> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>>> --
>>> Daniel-Constantin Mierla
>>> http://www.asipto.com
>>
>>
>>
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