20 Nov
2009
20 Nov
'09
7:02 p.m.
On 11/20/2009 05:32 PM, Daniel-Constantin Mierla wrote:
Hello,
On 20.11.2009 17:04 Uhr, Miklos Tirpak wrote:
This sounds good!
Hi Daniel,
On 11/20/2009 04:38 PM, Daniel-Constantin Mierla wrote:
also 487 (request canceled) has the
highest priority.
On 20.11.2009 9:53 Uhr, Miklos Tirpak wrote:
yes.
On 11/20/2009 12:58 AM, Andres Moya wrote:
> Dear all!
>
> Please help. I have problem dealing with recursive call in failure
> route.
>
> this route happen first time for authentication to external SIP
> provider (react on code 401), then it have response 480 i want to
> direct traffic to another operator via cr_route.
>
> First i relay INVITE and getting 401, then sending authentication,
> but provider gives 480. I can see it in a dump of SIP session. But
> my failure_route still thinking that reply code is 401 on second
> reply. Maybe because i dont understand well how branches concept
> work here? Or using kamailio 3.0? ;) Looks like it give me status
> code of first reply and ignoring actual code in reply. :( I don't
> know if it something with development version or my own
> misunderstanding. sorry
This is correct, the proxy must choose one of the two responses to
forward and 401 has higher precedence than 480 (RFC3261, 16.7:
"Choosing the best response"). The failure route always works on the
selected response as opposed to the last response received.
I think this is wrong
imo, if I got it right from your email, because
the failure route should work on a selected reply from the last set
of branches in serial forking.
Do you say that if I get 301 with couple of contacts, then in failure
route I create new branches, relay, all failed because of timeout
and/or busy, I get back in failure route with the 301?
I cannot drop all replies because maybe the reply I want to be sent
back to caller is from a previous branch. Think at:
A calls B
B phone gives busy
B has redirect to C in such case
C phone gives timeout
C has now redirect to voice mail
Voice mail returns server failure
If I need to drop the replies then I will send the 500 reply which is
wrong. If I do no drop replies, then it is hard to implement the
proper logic for different kinds of redirects:
- no answer
- busy
Yes, the above case is quite complicated, by default I think the 408
will be sent back because it is the lowest response code.
The priority list is: 6xx > 3xx > 4xx > 5xx.
The lowest response wins within the class but 401, 407, 415, 420, 484
are preferred over other 4xx responses.
If this is an issue then we can implement more sophisticated drop
commands that drop only selected branches, for example a single branch
that is being processed in failure route.
It just looks a bit unpredictable right now, mainly with what happens in
failure route because the reply code presented there is not what is
expected. So I would add a parameter:
t_drop_replies("all");
t_drop_replies("last");
It is not hard to implement at all. In SR is a flag to
mark the start of
last set of branches -- so getting the first branch in the last step
would be:
for(first_branch=t->nr_of_outgoings-1; first_branch>=0; first_branch--)
if(t->uac[first_branch].flags&TM_UAC_FLAG_FB)
break;
t_drop_replies("last") may be a bit confusing if it is called from
failure route, imagine the following case:
1. A calls B
2. B does not answer -> 408
3. B has redirect to C
4. C is busy -> 486
5. reply route is executed with the lowest response code received that
is 408 in this case.
If t_drop_replies("last") is called in 5) then it will drop the 486
although 408 is being processed. This means that it is hard to check in
5) whether to call t_drop_replies("last") because all the conditions
work on the 408. So "last" means the last branches not the last
processed by failure route.
Anyway, this may be a corner case, and it is still better than we
currently have. It may also make sense to drop a reply from reply_route
because the status code of the reply can be checked without being
affected by the other replies. Something like t_drop_replies("current")
But I would do it opposite, to have script simpler
(and be K compatible
and have uac_redirect and other k modules work as expected :-) ),
instead of drop function, have drop by default the replies from last set
of branches, and then t_keep_replies() so one ca decide to keep the
replies. Probably can be switched one way or another (K or S) but config
compatibility mode.
I am fine with this of course, we just need to have the drop capability
in one or another way.
Thanks,
Miklos
Cheers,
Daniel
Miklos
>
> Cheers,
> Daniel
>
>>
>> Try to add t_drop_replies() to the failure route block when the 401
>> is processed. This function drops all the existing replies, 401 in
>> your case, hence 401 will not be selected again when 480 is received.
>