Setting t_on_failure("FAILURE_ROUTE") before t_relay(), given a route block failure_route[FAILURE_ROUTE], as you are doing, should work.

--
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/

-- 
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free)
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/

On Wed, Jun 15, 2022 at 8:34 AM Antonio Couto <couto.a@gmail.com> wrote:

Thanks for your support, I am trying to do this but to be honest I don't know
how to arm the failure route for this case of "fr_inv_timer".

When I received reply 183 I use t_set_fr() function to set the new value for "fr_inv_timer",

do far so good, but I never received failure_route[0] when Kamailio terminate the call sending 408,

even calling like this:

t_on_failure("0");
t_relay();

I can't find on documentation how to do this.
Thanks a lot