Hello, Thanks for the suggestion. Callbacks for change of node state can be added easily enough and I agree they could be quite useful to other modules. Development is frozen currently but I can push to a separate branch if you're interested in testing? Cheers, Charles On 24 Apr 2015 13:42, "Vik Killa" &lt;vipkilla(a)gmail.com&gt; wrote: -- www.sipcentric.com Follow us on twitter @sipcentric <http://twitter.com/sipcentric> Sipcentric Ltd. Company registered in England & Wales no. 7365592. Registered office: Faraday Wharf, Innovation Birmingham Campus, Holt Street, Birmingham Science Park, Birmingham B7 4BB.

Another approach for HA is to use the dispatcher module as a front end loadbalancer and use health checking. Cheers Shane From: sr-users [mailto:sr-users-bounces@lists.sip-router.org] On Behalf Of Vik Killa Sent: Saturday, 25 April 2015 12:42 a.m. To: SIP Router - Kamailio (OpenSER) and SIP Express Router (SER) - Users Mailing List Subject: [SR-Users] add feature to dmq to allow for HA (heartbeat or pacemaker) Hello, I was looking to implement HA with 2 Kamailio machines. I am aware of the dmq module and I thought that would be a great place to start. The problem I see is that dmq module does not have any "failure" callback mechanism. For instance, if KamA sends dmq ping to KamB, and KamB does not respond (perhaps because it's down), then nothing happens. I looked into using the dmq API and checked the dmq code to see how send_message() function works, and I dont see any indication that there is a failure callback. I would be a great improvement to add this sort of functionality to dmq and then other modules or code can be written to use the API to detect when another Kam box is up or down. This could lead to another module like dmq_ha (I'm open to writing this) Thanks, V