[SR-Users] Kamailio propagates 180 and 200 OK OUT OF ORDER

Daniel-Constantin Mierla miconda at gmail.com
Thu Apr 9 08:41:42 CEST 2020


Hello,

I subscribed you manually to the list. See if works now.

Cheers,
Daniel

On 08.04.20 23:18, Luis Rojas G. wrote:
> Hello,
>
> I'd have to ask to IT department, to look into this. What would be the
> from for that email? Notice I do receive messages from
> sr-users-owner at lists.kamailio.org, notifying my posts need approval,
> for not being a list-member.
>
> Best regards,
>
> Lusi
>
> On 4/8/20 4:54 PM, Daniel-Constantin Mierla wrote:
>>
>> Hello,
>>
>> check the spam folder, especially if your email is hosted by some
>> large/public email provider. Or the email server logs, if it is
>> selfhosted.
>>
>> Cheers,
>> Daniel
>>
>> On 08.04.20 22:32, Luis Rojas G. wrote:
>>> Hello, Henning,
>>>
>>> No, I am not a member, and so every time I sent a message I receive
>>> the email with :
>>>
>>> "Your message to sr-users awaits moderator approval"
>>>
>>> I didn't receive any confirmation email or anything at all related
>>> to my subscription request.
>>>
>>> Best regards,
>>>
>>> Luis
>>>
>>> On 4/8/20 4:20 PM, Henning Westerholt wrote:
>>>>
>>>> Hello Luis,
>>>>
>>>>  
>>>>
>>>> I checked in the mailman checked, you seemed to be not subscribed
>>>> to the list. Have you received the confirmation e-mail and
>>>> confirmed it?
>>>>
>>>>  
>>>>
>>>> This is the date and time when you tried to subscribe:
>>>>
>>>>  
>>>>
>>>> Apr 07 23:08:35 2020 (15775) sr-users: pending Luis Rojas <luis dot
>>>> rojas at sixbell dot com>  181.73.XX.XX
>>>>
>>>>  
>>>>
>>>> Cheers,
>>>>
>>>>  
>>>>
>>>> Henning
>>>>
>>>>  
>>>>
>>>> -- 
>>>>
>>>> Henning Westerholt – https://skalatan.de/blog/
>>>> <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fskalatan.de%2Fblog%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534283207&sdata=nEXDRBQcCDLGpr1F1ljONe222cBc%2B%2F3ImrjA9x4FPkY%3D&reserved=0>
>>>>
>>>> Kamailio services – https://gilawa.com
>>>> <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgilawa.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534293197&sdata=wdwLQ3uIgs449VCD1JPEv4dWHJE9QF79T4B%2Fze0nVOs%3D&reserved=0>
>>>>
>>>>  
>>>>
>>>> *From:* Luis Rojas G. <luis.rojas at sixbell.com>
>>>> *Sent:* Wednesday, April 8, 2020 10:04 PM
>>>> *To:* miconda at gmail.com; Kamailio (SER) - Users Mailing List
>>>> <sr-users at lists.kamailio.org>; Henning Westerholt <hw at skalatan.de>
>>>> *Subject:* Re: [SR-Users] Kamailio propagates 180 and 200 OK OUT OF
>>>> ORDER
>>>>
>>>>  
>>>>
>>>> Hello, Daniel
>>>>
>>>> I will try this option.
>>>>
>>>> I tried the ASYNC, using async_ms_sleep, but it seems it's not
>>>> allowed in reply_route(). I wonder why. Documentation only mentions
>>>> request_route:
>>>>
>>>> https://kamailio.org/docs/modules/5.3.x/modules/async.html#async.f.async_ms_sleep
>>>> <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fkamailio.org%2Fdocs%2Fmodules%2F5.3.x%2Fmodules%2Fasync.html%23async.f.async_ms_sleep&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534293197&sdata=4OuKOdBgiWczJnw0td0AJ%2BbloLlcZqiN0Oqea6ez9SQ%3D&reserved=0>
>>>>
>>>>  
>>>>
>>>> if I use it in reply_route() kamailio does not even start.
>>>>
>>>>  0(22147) ERROR: <core> [core/cfg.y:3402]: yyparse(): misused
>>>> command async_ms_sleep
>>>>  0(22147) CRITICAL: <core> [core/cfg.y:3547]: yyerror_at(): parse
>>>> error in config file /etc/kamailio/kamailio.cfg, line 221, column
>>>> 23: Command cannot be used in the block
>>>>
>>>> ERROR: bad config file (1 errors)
>>>>
>>>> I wanted to introduce an artificial delay of just a few miliseconds
>>>> to 200 OK to INVITE.
>>>>
>>>> it's not just a problem about 180 and 200, but several other
>>>> conditions that will start to appear, like betwen ACK-Reinvite.
>>>>
>>>> Anyone reading is the list administrator? I tried to subscribe to
>>>> the list, bit it seems I am still not a member, so I don't receive
>>>> answers (unless I am copied directly) and can't post immediately,
>>>> only after moderator's approval.
>>>>
>>>>  
>>>>
>>>> Also, I can't answer all responses.
>>>>
>>>> Best regards,
>>>>
>>>>  
>>>>
>>>> Luis
>>>>
>>>> On 4/8/20 1:07 PM, Daniel-Constantin Mierla wrote:
>>>>
>>>>     Hello,
>>>>
>>>>     you have to keep in mind that Kamailio is a SIP packet router,
>>>>     not a telephony engine. If 180 and 200 replies are part of a
>>>>     call is not something that Kamailio recognize at its core. Its
>>>>     main goal is to route out as fast as possible what is received,
>>>>     by executing the configuration file script. Now, a matter of
>>>>     your configuration file, processing of some SIP messages can
>>>>     take longer than processing other. And the processing is done
>>>>     in parallel, a matter of children parameter (and tcp_children,
>>>>     sctp_children).
>>>>
>>>>     With that in mind, a way to try to cope better with the issue
>>>>     you face is to set route_locks_size parameter, see:
>>>>
>>>>       *
>>>>     https://www.kamailio.org/wiki/cookbooks/devel/core#route_locks_size
>>>>     <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.kamailio.org%2Fwiki%2Fcookbooks%2Fdevel%2Fcore%23route_locks_size&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534303196&sdata=7erZ3WkeBup8aeriNyVcc%2FkQSQLWeKUUcUx0Ty2uQp0%3D&reserved=0>
>>>>
>>>>     Probably is what you look for.
>>>>
>>>>     But if you want more tight constraints, like when receiving a
>>>>     180 after a 200ok and not route it out, you have to make the
>>>>     logic in configuration file by combining modules such as dialog
>>>>     or htable (as already suggested).
>>>>
>>>>     Cheers,
>>>>     Daniel
>>>>
>>>>     On 08.04.20 16:04, Luis Rojas G. wrote:
>>>>
>>>>         Hi, Henning,
>>>>
>>>>          
>>>>
>>>>         No need to be ironic. As I mentioned on my first post, I
>>>>         tried stateful proxy and I observed the same behavior.
>>>>
>>>>         /"I tried using stateful proxy and I obtained the same
>>>>         result."/
>>>>
>>>>         The asynchronous sleep seems promising. I will look into it.
>>>>
>>>>         Thanks,
>>>>
>>>>          
>>>>
>>>>         Luis
>>>>
>>>>
>>>>         On 4/8/20 9:30 AM, Henning Westerholt wrote:
>>>>
>>>>             Hi Luis,
>>>>
>>>>              
>>>>
>>>>             I see. Well, you want to use Kamailio as a stateless
>>>>             proxy, on the other hand it should do things that are
>>>>             inherently stateful. 😉
>>>>
>>>>              
>>>>
>>>>             As mentioned, have a look to the dialog module to track
>>>>             the state of dialogs that you process. This will not
>>>>             work in a stateless mode, though.
>>>>
>>>>              
>>>>
>>>>             You can also use the htable module to just store some
>>>>             data about the processed messages in a shared memory
>>>>             table and use this to enforce your ordering. There is
>>>>             also the option to do an asynchronous sleep (with the
>>>>             async) module on the message that you want to delay but
>>>>             still processing other messages during it.
>>>>
>>>>              
>>>>
>>>>             Cheers,
>>>>
>>>>              
>>>>
>>>>             Henning
>>>>
>>>>              
>>>>
>>>>             -- 
>>>>
>>>>             Henning Westerholt – https://skalatan.de/blog/
>>>>             <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fskalatan.de%2Fblog%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534313186&sdata=DQ49A2ttIOZMqKcs5q%2BFcaqEzUJBFev%2FsKfFSbctKvg%3D&reserved=0>
>>>>
>>>>             Kamailio services – https://gilawa.com
>>>>             <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgilawa.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534313186&sdata=MooHgSRmMmruaIOAziP93d4IObqg%2FNGolH9GvFMRSvI%3D&reserved=0>
>>>>
>>>>
>>>>              
>>>>
>>>>             *From:* Luis Rojas G. <luis.rojas at sixbell.com>
>>>>             <mailto:luis.rojas at sixbell.com>
>>>>             *Sent:* Wednesday, April 8, 2020 3:00 PM
>>>>             *To:* Henning Westerholt <hw at skalatan.de>
>>>>             <mailto:hw at skalatan.de>; Kamailio (SER) - Users Mailing
>>>>             List <sr-users at lists.kamailio.org>
>>>>             <mailto:sr-users at lists.kamailio.org>
>>>>             *Subject:* Re: [SR-Users] Kamailio propagates 180 and
>>>>             200 OK OUT OF ORDER
>>>>
>>>>              
>>>>
>>>>             Hello, Henning,
>>>>
>>>>              
>>>>
>>>>             I am worried about this scenario, because it's a
>>>>             symptom of what may happen in other cases. For
>>>>             instance, I've seen that this operator usually sends
>>>>             re-invites immediate after sending ACK.   This may
>>>>             create race conditions like 3.1.5 of RFC5407
>>>>
>>>>             https://tools.ietf.org/html/rfc5407#page-22
>>>>             <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftools.ietf.org%2Fhtml%2Frfc5407%23page-22&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534323186&sdata=qsPRiqiZ9H9ACCISTxxMEhoVz4g0iY1u78CNfCtq3%2F8%3D&reserved=0>
>>>>
>>>>             I'd understand that one happens because of packet loss,
>>>>             as it's in UDP's nature, but in this case it would be
>>>>             artificially created by Kamailio. if there was no
>>>>             problem at network level (packet loss, packets
>>>>             following different path on the network and arriving
>>>>             out of order), why Kamailio creates it?
>>>>
>>>>             I'd expect that the shared memory is used precisely for
>>>>             this. If an instance of kamailio receives a 200 OK, it
>>>>             could check on the shm and say "hey, another instance
>>>>             is processing a 180 for this call. Let's wait for it to
>>>>             finish" (*). I know there could still be a problem, the
>>>>             instance processing the 180 undergoes a context switch
>>>>             just after it receives the message, but before writing
>>>>             to shm, but it would greatly reduce the chance.
>>>>
>>>>              
>>>>
>>>>             In our applications we use a SIP stack that always
>>>>             sends messages to the application in the same order it
>>>>             receives them, even though is multi-threaded and
>>>>             messages from the network are received by different
>>>>             threads. So, they really syncronize between them. Why
>>>>             Kamailio instances don't?
>>>>
>>>>             I am evaluating kamailio to use it as a dispatcher to
>>>>             balance load against our several Application Servers,
>>>>             to present to the operator just a couple of entrance
>>>>             points to our platform (they don't want to establish
>>>>             connections to each one of our servers). This operator
>>>>             is very difficult to deal with. I am sure they will
>>>>             complain something like "why are you sending messages
>>>>             out of order? Fix that". The operator will be able to
>>>>             see traces and check that messages entered the Kamailio
>>>>             nodes in order and left out of order. They will not
>>>>             accept it.
>>>>
>>>>             (*) Not really "wait", as it would introduce a delay in
>>>>             processing all messages. it should be like putting it
>>>>             on a queue, continue processing other messages, and go
>>>>             back to the queue later.
>>>>
>>>>             Well, thanks for your answer.
>>>>
>>>>             Luis
>>>>
>>>>
>>>>
>>>>              
>>>>
>>>>
>>>>             On 4/8/20 3:01 AM, Henning Westerholt wrote:
>>>>
>>>>                 Hello Luis,
>>>>
>>>>                  
>>>>
>>>>                 as the 1xx responses are usually send unreliable
>>>>                 (unless you use PRACK), you should not make any
>>>>                 assumption on the order or even the arrival of this
>>>>                 messages. It can also happens on a network level,
>>>>                 if send by UDP.
>>>>
>>>>                  
>>>>
>>>>                 Can you elaborate why you think this re-ordering is
>>>>                 a problem for you?
>>>>
>>>>                  
>>>>
>>>>                 One idea to enforce some ordering would be to use
>>>>                 the dialog module in combination with reply routes
>>>>                 and the textops(x)  module.
>>>>
>>>>                  
>>>>
>>>>                 About the shared memory question – Kamailio
>>>>                 implement its own memory manager (private memory
>>>>                 and shared memory pool).
>>>>
>>>>                  
>>>>
>>>>                 Cheers,
>>>>
>>>>                  
>>>>
>>>>                 Henning
>>>>
>>>>                  
>>>>
>>>>                  
>>>>
>>>>                 -- 
>>>>
>>>>                 Henning Westerholt – https://skalatan.de/blog/
>>>>                 <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fskalatan.de%2Fblog%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534333185&sdata=5EdaaG7DbrB%2FIUdWfTwavZo1Lt2ouL8OReF8g%2Bie47Y%3D&reserved=0>
>>>>
>>>>                 Kamailio services – https://gilawa.com
>>>>                 <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgilawa.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534333185&sdata=Fm8pBnl3o2tUIrQ%2BQnPrSqKjwsnGyp6McNnb%2FeLhj5U%3D&reserved=0>
>>>>
>>>>
>>>>                  
>>>>
>>>>                 *From:* sr-users
>>>>                 <sr-users-bounces at lists.kamailio.org>
>>>>                 <mailto:sr-users-bounces at lists.kamailio.org> *On
>>>>                 Behalf Of *Luis Rojas G.
>>>>                 *Sent:* Tuesday, April 7, 2020 10:43 PM
>>>>                 *To:* sr-users at lists.kamailio.org
>>>>                 <mailto:sr-users at lists.kamailio.org>
>>>>                 *Subject:* [SR-Users] Kamailio propagates 180 and
>>>>                 200 OK OUT OF ORDER
>>>>
>>>>                  
>>>>
>>>>                 Good day,
>>>>
>>>>                 I am testing the dispatcher module, using Kamailio
>>>>                 as stateless proxy. I have a pool of UAC (scripts
>>>>                 in SIPP) and a pool of UAS (also scripts in SIPP)
>>>>                 for the destinations. Kamailio version is
>>>>                 kamailio-5.3.3-4.1.x86_64.
>>>>
>>>>                 Problem I have is, if UAS responds 180 and 200 OK
>>>>                 to Invite immediately, sometimes they are
>>>>                 propagated out of order. 200 OK before 180, like this :
>>>>
>>>>                 UAS is 172.30.4.195:5061. UAC is 172.30.4.195:5080.
>>>>                 Kamailio is 192.168.253.4:5070
>>>>
>>>>                 Difference between 180 and 200 is just about 50
>>>>                 microseconds.
>>>>
>>>>                 My guess is that both messages are received by
>>>>                 different instances of Kamailio, and then because
>>>>                 of context switches, even though the 180 is
>>>>                 received before, that process ends after the
>>>>                 processing of 200. However, I had the idea that in
>>>>                 order to avoid these problems the kamailio
>>>>                 processes synchronized with each other using a
>>>>                 shared memory. I tried using stateful proxy and I
>>>>                 obtained the same result.
>>>>
>>>>                 By the way, anyone has any idea about how
>>>>                 Kamailio's share memory is implemented? It clearly
>>>>                 does not use the typical system calls shmget(),
>>>>                 shmat(), because they are not shown by ipcs command.
>>>>
>>>>                 Before posting here I googled, but I couldn't find
>>>>                 anything related to this. I can't believe I am the
>>>>                 only one who ever had this problem, so I guess I am
>>>>                 doing something wrong...
>>>>
>>>>                 Please, any help. I'm really stuck on this.
>>>>
>>>>                 Thanks.
>>>>
>>>>                 -- 
>>>>
>>>>              
>>>>
>>>>             -- 
>>>>
>>>>             Luis Rojas
>>>>
>>>>             Software Architect
>>>>
>>>>             Sixbell
>>>>
>>>>             Los Leones 1200
>>>>
>>>>             Providencia
>>>>
>>>>             Santiago, Chile
>>>>
>>>>             Phone: (+56-2) 22001288
>>>>
>>>>             mailto:luis.rojas at sixbell.com
>>>>
>>>>             http://www.sixbell.com <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.sixbell.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534343177&sdata=h%2FYaeUuoMfGSXDqikgdpNbQAw5B%2FCg3EBkhOEdA%2FwKM%3D&reserved=0>
>>>>
>>>>          
>>>>
>>>>         -- 
>>>>
>>>>         Luis Rojas
>>>>
>>>>         Software Architect
>>>>
>>>>         Sixbell
>>>>
>>>>         Los Leones 1200
>>>>
>>>>         Providencia
>>>>
>>>>         Santiago, Chile
>>>>
>>>>         Phone: (+56-2) 22001288
>>>>
>>>>         mailto:luis.rojas at sixbell.com
>>>>
>>>>         http://www.sixbell.com <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.sixbell.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534343177&sdata=h%2FYaeUuoMfGSXDqikgdpNbQAw5B%2FCg3EBkhOEdA%2FwKM%3D&reserved=0>
>>>>
>>>>
>>>>
>>>>         _______________________________________________
>>>>
>>>>         Kamailio (SER) - Users Mailing List
>>>>
>>>>         sr-users at lists.kamailio.org <mailto:sr-users at lists.kamailio.org>
>>>>
>>>>         https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users <https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.kamailio.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fsr-users&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534353171&sdata=Ka6aW1zZ%2Fnbsr%2FKlE2l3ZJn0o5Io328x%2FNHO7N461vA%3D&reserved=0>
>>>>
>>>>     -- 
>>>>
>>>>     Daniel-Constantin Mierla -- www.asipto.com <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.asipto.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534363169&sdata=tzurqeb3UretL9Oj9M096Wx1K30cBfaspcpdT9fD1Es%3D&reserved=0>
>>>>
>>>>     www.twitter.com/miconda <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.twitter.com%2Fmiconda&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534363169&sdata=om1ZWElalA8cfv8AOGbLYmq3PMFacn4%2B5DDIxcysJq8%3D&reserved=0> -- www.linkedin.com/in/miconda <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.linkedin.com%2Fin%2Fmiconda&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534373163&sdata=VHHB9eYyNtTa%2B0%2BsXY5fWekVeF6wBmOSTzlRzNiwZ20%3D&reserved=0>
>>>>
>>>>  
>>>>
>>>> -- 
>>>> Luis Rojas
>>>> Software Architect
>>>> Sixbell
>>>> Los Leones 1200
>>>> Providencia
>>>> Santiago, Chile
>>>> Phone: (+56-2) 22001288
>>>> mailto:luis.rojas at sixbell.com
>>>> http://www.sixbell.com <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.sixbell.com%2F&data=02%7C01%7C%7C1fc802f8e5fc4572ad2908d7dbfefc67%7Cab4a33c2b5614f798601bc921698ad08%7C0%7C0%7C637219760534383154&sdata=k7rDRhwhFCrLmcnQZejZzXKBAkxmcvF8aHacWg27dtg%3D&reserved=0>
>>>
>>>
>>> -- 
>>> Luis Rojas
>>> Software Architect
>>> Sixbell
>>> Los Leones 1200
>>> Providencia
>>> Santiago, Chile
>>> Phone: (+56-2) 22001288
>>> mailto:luis.rojas at sixbell.com
>>> http://www.sixbell.com
>> -- 
>> Daniel-Constantin Mierla -- www.asipto.com
>> www.twitter.com/miconda -- www.linkedin.com/in/miconda
>
>
> -- 
> Luis Rojas
> Software Architect
> Sixbell
> Los Leones 1200
> Providencia
> Santiago, Chile
> Phone: (+56-2) 22001288
> mailto:luis.rojas at sixbell.com
> http://www.sixbell.com

-- 
Daniel-Constantin Mierla -- www.asipto.com
www.twitter.com/miconda -- www.linkedin.com/in/miconda

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