[SR-Users] t_check_trans return false on CANCEL

Thu May 27 12:16:59 CEST 2010

On May 27, 2010 at 11:50, Ernest Mavrel <ernest.mavrel at novatel.si> wrote:
> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

Please try to send mails as plain text and not as html.

> Hello,<br>
> <br>
> Kamailio v 1.4.2<br>
> I have problems with canceling calls. When CANCEL arrive to kamailio
> function t_check_trans always return false. Cancel message arrive after
> 75s. I was try with "<code></code>t_newtran", but without success. The
> only thing which I found that could be a problem is different branch on
> INVITE and CANCEL. I changed "via1_matching" to "0", but problem is
> still there.<br>

via1_matching is only for pre-3261 transactions to support broken UACs.
This means it's used only if the via branch parameter _does_ _not_ start
with "z9hG4bK". If the transaction is 3261-style, the via1_matching
parameter is _ignored_.
In your case the branch parameter does start with "z9hG4bK".

> What could be wrong?<br>

The CANCEL via branch does not match the INVITE, so the CANCEL is not
matched to the existing INVITE transaction. You need to fix your user
agents.

[...]

Andrei