Hello Daniel,

A URI param doesn't sound bad at all for this purpose, and works like a charm! I believe the parameter never makes it to the receiving end when using regular dispatcher functionality, as the R-URI is not rewritten and only the $du variable is set with this URI, which never appears in the SIP message anywhere, right? So there's some degree of elegance here as well :-D.

Thanks again for the workaround, I've been working on this for a while...

Best regards,
George

On 20 December 2017 at 17:26, Daniel-Constantin Mierla <miconda@gmail.com> wrote:

Hello,

an workaround would be to add a custom parameter to the destination value, like sip:1.2.3.4:5060;sid=1. Unknown parameters should be ignored by the receiving party. Or if you have only two records with same address, add to one ";transport=udp".

Of course, coding in C to make it easier in config would be the elegant solution.

Cheers,
Daniel


On 20.12.17 15:32, George Diamantopoulos wrote:
Hello Daniel,

Thanks for the reply. Unfortunately I can't really use the database records to achieve what I want. The example in my previous message didn't show this, but I would like to be able to differentiate between the following:

+----+-------+-------------------------+-------+----------+-----------------------------+
| id | setid | destination             | flags | priority | attrs                       |
+----+-------+-------------------------+-------+----------+-----------------------------+
|  1 |     1 | sip:111.111.11.1:5060   |     8 |        0 | socket=udp:44.44.44.1:5060  |
|  2 |    10 | sip:
111.111.11.1:5060   |     8 |        0 | socket=udp:55.55.55.1:5060  |
+----+-------+-------------------------+-------+----------+-----------------------------+

In this case, how can I tell which destination went down? The URI is the same, but the sockets differ for each id.

If only $ru is available in these event routes, I can't query the database because $ru matches both records. If I can't access the socket used with a PV, is there any way to have access to either the id or the setid for the destination for which the event was generated?

Thanks!

BR,
George

On 20 December 2017 at 10:57, Daniel-Constantin Mierla <miconda@gmail.com> wrote:

Hello,

those event routes are executed with a so called faked request (a request generated internally, unrelated to the OPTIONS request sent to the wire), apart of request uri, the rest of values are not related to the dispatcher records.

To get access to other attributes of dispatcher records in a straight way in the config, it would require C coding, Anyhow, even now using scripting, you can try with sql queries to database or rpc commands execution via jsonrpcs module and then parse the result using jansson module.

Cheers,
Daniel


On 18.12.17 13:33, George Diamantopoulos wrote:
Hello all,

I use the dispatcher module extensively for load balancing and fail-over. My kamailio instance is multihomed, and I use the "socket" attribute to determine which socket SIP messages should use for each dispatcher destination, as such:

+----+-------+-------------------------+-------+----------+-----------------------------+
| id | setid | destination             | flags | priority | attrs                       |
+----+-------+-------------------------+-------+----------+-----------------------------+
|  1 |     0 | sip:192.168.0.1:5060    |     8 |        0 | socket=udp:10.10.10.1:5060  |
|  2 |     1 | sip:111.111.11.1:5060   |     8 |        0 | socket=udp:44.44.44.1:5060  |
|  3 |     1 | sip:222.222.22.2:5060   |     8 |        0 | socket=udp:55.55.55.1:5060  |
+----+-------+-------------------------+-------+----------+-----------------------------+


The dispatcher module uses OPTIONS to probe each destination for availability. When a destination goes down or up, the respective event-route is executed.

What I need to do is to be able to "capture" the sending socket used for this probing when a destination becomes unavailable or available in the event-routes. The $fs variable is set, but unfortunately its value does not make sense. Here's an example route and the results that are printed:

event_route[dispatcher:dst-down] {
    xlog("L_ERR", "Destination down: $rm $ru ($du) $ds $fs $Ru $T_req($fs) $T_req($Ru)\n");
}

Now say destination with id = '2' goes down. This is what I get in the logs for the event_route above:

ERROR: <script>: Destination down: OPTIONS sip:
111.111.11.1:5060 (sip:192.168.0.1:5060) Contact: <sip:111.111.11.1:5060> udp:10.10.10.1:5060 <null> <null> <null>

The xlog PV/log mapping for the above line is the following:

$rm: OPTIONS
$ru: sip:111.111.11.1:5060
$ds: Contact: <sip:111.111.11.1:5060>
The rest are $null. $ru and $ds are consistent with the actual destination being probed, $du and $fs are not (the are set to values corresponding to id = '1', for some reason).

This log line is, of course, inaccurate. Not only does it not make sense, but also this is not consistent with messages captured on network interfaces using sngrep: Kamailio does indeed behave as it should, the OPTIONS is sent out to 111.111.11.1 from socket
udp:44.44.44.1:5060. But this is not reflected in the log entry above when the event_route is executed.

Now the weird part is that this OPTIONS "transaction" (which is locally generated by kamailio) has the $du PV set to the value of another destination (namely the that of id = '1'). As a result, the $fs PV is consistent with that choice for $du. I can verify with sngrep that this is not the case in reality, as the request was sent to destination id = '2' from the correct socket as indicated above.

What I would like to ask is whether these "OPTIONS" used by dispatcher for probing go through the request_route processing at some point. This is the only way that would explain the $du PV being set to a false value. If yes, is there any way to prevent this from happening? I need to be able to access the $fs PV when a destination goes up or down, and I can't have any other configuration file routes interfering with that. Thanks!

Best regards,
George


_______________________________________________
Kamailio (SER) - Users Mailing List
sr-users@lists.kamailio.org
https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users

-- 
Daniel-Constantin Mierla
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio Advanced Training - www.asipto.com
Kamailio World Conference - May 14-16, 2018 - www.kamailioworld.com


-- 
Daniel-Constantin Mierla
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio Advanced Training - www.asipto.com
Kamailio World Conference - May 14-16, 2018 - www.kamailioworld.com