Today was a very productive day. For those who don't know, I have coded a DNS plugin that works with PowerDNS that allows FusionPBX (and FreeSWITCH of course) to run in load-balanced mode. This will allow a PBX network to have many servers across the globe and your customers will connect to them depending on some network metrics. I should say that this approach doesn't need any SIP proxy servers in front of VoIP servers (many people use Kamailio for this). The magic happens in the VoIP servers. They know where to bridge the call and all the logic happens within the FreeSWITCH, which is very cool if you ask me.
The big difference between my software against others is that the network decision is based on the actual network metrics (traceroutes, pings) and not just a geolocalization like most of load balancing services such as Amazon WS DNS service.
The new release I am working on is 1.2.3. Among the bug fixes I have been doing, it has NAPTR record support. Some IP phones such as Polycom need NAPTR records to know what SRV records it should use.
Another cool capability that was requested from a customer of mine is the ability to do server groups. Grouping is very useful, for example, all servers in the same data center should belong to the same group. With this, all metrics shouldn't be done as the metric for server A would be almost the same for server B if they are in the same location. This was thought to get around data centers that have blocked the traffic, such as Azure where you can not do traceroutes or pings.
Good luck!
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