This page outlines the various option available to create high availability for a VoIP PBX. Some are generic solutions while others are PBX specific. Some are complete HA solutions while others are half-baked scripts that do some things but not others.
Before you select a HA solution, carefully read this page on creating / selecting a High Availability solution (see Asterisk High Availability Design )
These solutions are proprietary/custom code and Asterisk bundled together to make a distribution; and/or a module which extends such a distribution. The benefit of these solutions is that because they are bundled/are part of a distribution, they are simple to install. The down side is that they lack peer autonomy, advanced failure detection, and other features listed on the Asterisk High Availability Design page. (eg: they use DRBD, use simplistic Asterisk process ID alive to detect failure, etc.). These solutions are ideally suited to home office / small office scenarios with low demands/expectations of HA, and low skills required of those performing the installation.
Before you select a HA solution, carefully read this page on creating / selecting a High Availability solution (see Asterisk High Availability Design )
PBX Specific Solutions
-These solutions provide clusters that are PBX specific. As noted on the Asterisk High Availability Design wiki page, these solutions create clusters at the Application level and are deeply PBX aware, environmentally aware, trunk aware, etc. These solutions are usually deployed in mission critical call center environments (e.g.: 911/PSAP) and high-uptime commercial environments. The benefit of these solutions is complete peer autonomy and extensive detection, and all features in an integrated solution (heartbeat, data synchronizations, failure detection, sharing IP, etc.). The downside of these solutions is that they are PBX specific, so if your PBX software (eg: Asterisk, 3CX, FreeSwitch) is not listed below then you can't use these solutions, and they require more OS and PBX skills to install.- HAAst (High Availability for Asterisk) from Telium adds high availability / clustering to any pair of Asterisk servers. The High Availability for Asterisk (HAAst) add-on offers rapid automatic failover of a failed peer, total peer autonomy, IP sharing, advanced peer health detection, intelligent synchronization of files and databases, etc. HAAst also supports manual promote/demote for maintenance, a command line interface, a telnet interface, a web based interface, and a developer API. Installation is straight forward, with no additional hardware required, no additional or complex heartbeat/cluster/etc software required either. HAAst is available in Free and Commercial editions, and is in use at call centers, hospitals, and other high-uptime environments. HAAst is targeted at large commercial installations but a Free edition is available for anyone. HAAst operates at the OS level and is compatible with all Asterisk variations (FreePBX, Elastix, Thirdlane, Digium). See High Availability Asterisk (HAAst) for more information.
Distribution Specific HA Modules/Platforms
These solutions are proprietary/custom code and Asterisk bundled together to make a distribution; and/or a module which extends such a distribution. The benefit of these solutions is that because they are bundled/are part of a distribution, they are simple to install. The down side is that they lack peer autonomy, advanced failure detection, and other features listed on the Asterisk High Availability Design page. (eg: they use DRBD, use simplistic Asterisk process ID alive to detect failure, etc.). These solutions are ideally suited to home office / small office scenarios with low demands/expectations of HA, and low skills required of those performing the installation.
- SARK-HA from Aelintra Telecom offers High Availability Asterisk out-of-the box. The Sark 200 is a complete PBX in a box solution, using a low-power ARM process all in the size of a deck of cards. Real-time failover takes less than 20 seconds to complete and includes support for ISDN PRI circuits. The servers are kept in synch using rsync (so no shared DRBD disk!). Wiki pages HERE. System also includes multi-tenant and a fully integrated provisioning system with zero touch, DHCP-free set-up for multicast capable phones... see