kamailio-etcd-dispatcher

Adds service discovery for Asterisk to Kamailio, letting Kamailio dynamically discover Asterisk boxes, and then load balance to them. Modifies a Kamailio dispatcher to have Kamailio act as a load balancer for machines discovered with etcd.

This tool automatically builds a dispatcher.list for Kamailio (using the Kamailio Dispatcher), in order to dynamically load balance Asterisk hosts, e.g. for when they're run under Fleet in CoreOS. In short, you run one instance as a side-kick to Kamailio (in "dispatcher mode") and then another instance as a side-kick to each Asterisk instance (in "announcer mode")

kamailio-etcd-dispatcher is part of a High Availability setup with Asterisk under CoreOS & Docker. Make sure you check out docker-asterisk which has more information on running a high availability Asterisk setup using CoreOS & Docker. Additionally, I presented information about this tool at Astricon 2015, and my presentation slide show is available @ astricon.dougbtv.com (hopefully youtube video coming soon, too)

Install

Install globally so you can just run it:

npm install -g kamailio-etcd-dispatcher

Basic Usage

Basic usage can be found a la:

[user@localhost ~]$ etcd-dispatcher --help

Usage: node etcd-dispatcher [options]

Options:
   -e, --etcdhost       Set etcd host or ip address  [127.0.0.1]
   -o, --etcdport       Set etcd host or ip address  [4001]
   -r, --rootkey        Set etcd root key to use  [asterisk]
   -t, --timeout        Timeout before heartbeat pulse check fails (in milliseconds)  [20000]
   -l, --listpath       Path of the dispatcher.list file [dispatcher mode only]  [/etc/kamailio/dispatcher.list]
   -a, --announce       Start in "announce" mode (defaults to dispatcher mode)
   -i, --announceip     IP Address to announce [announce mode only]  [127.0.0.1]
   -n, --announcename   Name to use in announcement, is key in etcd [announce mode only]
   -p, --announceport   Port to announce [announce mode only]  [false]
   -w, --weight         Percentage of calls to distribute to this node [announce mode only]  [false]
   -h, --heartbeat      Time between heartbeat pulses [announce mode only]  (in milliseconds)  [5000]
   --logdisable         Disable logging (not always useful...)
   --logfile            Log specifically to a file  [false]

Usage examples

You can always get help with:

etcd-dispatcher --help

Run an dispatcher like:

etcd-dispatcher --etcdhost 192.168.1.1 --timeout 25000

Run an announcer like:

etcd-dispatcher --announce --etcdhost 192.168.1.1 --timeout 5500

More information

Works in both "dispatcher" mode, which sits next to a Kamailio box and watches for Asterisk to announce itself. And in "announce" mode where it announces to Kamailio that it's available (and pulses heartbeats to it).