Tech

Different IP Addresses for Failover

Published on:

December 5, 2014

Failover capabilities are essential for ensuring uninterrupted service in PBX installations, especially with the growing use of high-bandwidth wireless connections like 4G. PBX systems traditionally use LAN-based IP addresses, but dynamically switching to a public IP address during failover has posed challenges. To address this, we've introduced a new feature - the PBX periodically probes a specified URL to detect its public IP address and adjusts the routing table accordingly. This feature simplifies the process, eliminating the need for complex scripts and allowing systems to automatically switch to the correct IP during failover, ensuring continuous operation. The feature will be available in version 5.2.5.

Failover is an important feature for most PBX installations. With the availability of high-bandwidth wireless like 4G, it becomes more and more popular to use the wireless connection when the primary landline internet access becomes unavailable.

For a long time, we've made it possible for the PBX to run in the LAN, which replaced the local IP address with publicly routable IP addresses. The IP replacement list was already a topic of many forum discussions.

When it comes to dynamically switching the presented IP address in the case of a failover, however, we were in trouble. In theory, it'd be possible to run a script that tests for the public IP address and then uses the REST interface and changes the routing table. Not everyone is a bash wizard, however, and it would even require different scripts for the different operating systems.

This was the reason why we went ahead and added a new feature that takes the URL for probing the public IP address of the PBX and an interval time value. The PBX will then periodically download the URL and set the public IP address of the PBX accordingly. The public IP address can be referenced with the magic name “public” in the routing list, like this:

192.168.0.0/255.255.0.0/192.168.1.1 0.0.0.0/0.0.0.0/public

Then the PBX would present 192.168.1.1 in the LAN and whatever-is-the-public-address in all other cases.

In the response from the web server, the PBX expects an IP address in human readable format, or in JSON-format, where the object must contain a entry called “ip” (for example, see http://myjsonip.appspot.com/). It's possible to use public servers, but obviously you can also use your own servers.

The failover will obviously take some time. The polling interval determines how fast the change is being detected. Obviously there's a tradeoff between polling (too) often and the time it takes to reflect the new address.

The new settings will be available right under the replacement list in 5.2.5.

Latest Articles

View All

Why Vodia is the Ideal PBX for Microsoft Environments

Many organizations rely on Microsoft as the foundation of their daily operations, but their communication systems often exist in parallel rather than in harmony. Vodia closes that gap by bringing telephony into the same environment where teams already work, turning separate systems into one connected structure. This approach removes friction between platforms, simplifies management, and gives IT teams better control and visibility over daily communication. It also creates a more seamless experience for employees, reduces operational overhead, and builds a stronger, more flexible foundation that supports growth, collaboration, and long-term scalability.

October 17, 2025

Vodia to Attend CVxExpo 2025 in Glendale, Arizona

Vodia will be attending CVxExpo 2025 in Glendale, Arizona, from November 3–5. Sales Engineer Eric Altman will be on site to meet with current and prospective partners, demonstrating how Vodia’s PBX solutions can strengthen technology roadmaps for 2026. This year, Vodia highlights new integrations with ActiveCampaign, Freshdesk, HighLevel, Microsoft 365, Microsoft Presence, monday.com, and Odoo Cloud, along with enhanced call center capabilities such as agent activity dashboards, call recordings, and transcription features. Partners and attendees can schedule meetings with Eric to learn more about scalable, feature-rich, and cost-effective telecommunications solutions built for enterprises and SMBs.

October 14, 2025

Enterprise Call Analytics: Real-Time Insights Built Right Into Your PBX

Vodia Enterprise Call Analytics gives businesses comprehensive, real-time insights into every aspect of their call operations. Built natively into the PBX, it delivers live, color-coded dashboards, detailed call records, smart filtering, and exportable data. Enterprises can track key metrics such as answer rates, call volume, peak hours, talk times, and top performers, while also monitoring call quality through integrated MOS scoring. By turning call data into actionable intelligence, Vodia helps organizations optimize team productivity, improve customer experience, manage costs effectively, streamline workflows efficiently, and make smarter, data-driven decisions that contribute directly to revenue, operational performance, and long-term ROI.

October 10, 2025