Hello, I have a question about LCR which I have been unable to solve. I have 4 upstream carrier gateways owned by 2 carriers. Each carrier provides a primary and secondary gateway for load balancing purposes. On a 5XX error I am trying to send the same call to the other carrier. If both carriers reject the call with 5XX, I allow the response to go downstream to my asterisk server. The issue I am running into is that in a scenario where both my carriers respond with a 5XX, I end up presenting the same call to all 4 gateways. I would like to present the call to one gateway on each carrier and not try the same carriers second gateway for the same call. Here is what is happening now:
ASTERISK --> INVITE --> KAMAILIO INVITE --> CARRIER A/GATEWAY 1 <-- 5XX Error INVITE --> CARRIER A/GATEWAY 2 <-- 5XX Error INVITE --> CARRIER B/GATEWAY 1 <-- 5XX Error INVITE --> CARRIER B/GATEWAY 2 <-- 5XX Error KAMAILIO --> 5XX Error --> ASTERISK
OR any combination of the above... i.e.
ASTERISK --> INVITE --> KAMAILIO INVITE --> CARRIER A/GATEWAY 1 <-- 5XX Error INVITE --> CARRIER B/GATEWAY 2 <-- 5XX Error INVITE --> CARRIER B/GATEWAY 1 <-- 5XX Error INVITE --> CARRIER A/GATEWAY 2 <-- 5XX Error KAMAILIO --> 5XX Error --> ASTERISK
What I want to happen is:
ASTERISK --> INVITE --> KAMAILIO INVITE --> CARRIER A/GATEWAY 1 or 2 <-- 5XX Error INVITE --> CARRIER B/GATEWAY 1 or 2 <-- 5XX Error KAMAILIO --> 5XX Error --> ASTERISK
I tried dealing with the issue using some flags on the gateway, but i couldn't get the logic to work properly. Here is the path I was heading down, but my plan fell apart after some testing.
CARRIER A has a gateway flag of "1" CARRIER B has a gateway flag of "2"
failure_route[1]{ $var(gw_flag) = $avp(i:712);
while(next_gw()){ if($var(gw_flag) != $avp(i:712)){ xlog("L_INFO","Found an LCR destination which is different than current, routing. ($ci)"); t_on_reply("1"); t_on_failure("1"); t_relay(); exit; }else{ xlog("L_INFO","The next destination in LCR has the same AVP flag, skipping. ($ci)"); } }
# let the reply go upstram - it is the default action xlog("L_ERR", "No Next Gateway - M=$rm RURI=$ru F=$fu T=$tu IP=$si ID=$ci\n"); exit; }
Any help would be greatly appreciated.
Thanks, Geoff