[SR-Users] Loadbalancing proxy using DNS SRV instead of dispatcher

[Jon Bonilla (Manwe)]

El Fri, 17 Apr 2015 09:41:55 +0100
Cezary Siwek <cezary.siwek at nexmo.com> escribió:

> Hi,
> 
> I haven't tried it mysefl (will probably do it in a near future) but 
> there is core configuration parameter to be enabled.
> http://www.kamailio.org/wiki/cookbooks/4.2.x/core#dns_srv_lb
> 
> As we speak, some of our clients reported similar issue when connection 
> to us using FreeSWITCH and setting weight to 0 seem to resovle the issue 
> (it was prosposed solution on freeswitch mailing list)
> 
> We internally don't do SRV LB in outbound direction but probably will so 
> please come back with your results.
> 


I had the issue in the past and here's how it was solved:

- When sending your "first" request to the server resolving it by DNS, you can
  store the destination IP in a hash table (callid--> IP) using onsend_route

The kamailio script should check something like this: 

1: Initial request. Is the callid in hash table? 
  Yes --> Don't resolve DNS and send it to the stored IP
  NO -->  Use DNS to send it and store the IP using onsend_route

If you set the autoexpire of keys to 3-4 secs it will work well.



cheers,

Jon