FreePBX includes a backup script which causes high CPU and IO latency when it runs. During this time the entire system becomes unresponsive, and call quality may suffer. HAAst will accurately detect that the server has become unresponsive and initiate a failover.
Customers don’t usually realize the system degradation caused by the FreePBX backup script as the script normally runs late at night. However, if the CPU and/or IO latency become severe, processes may hang/crash/use 100% CPU.
The solution is to start by dealing with the root cause: disable the FreePBX backup script. This script is known to cause a variety of other system related issues. Instead use a high quality backup program (free or commercial). If that is not an option, Telium can assist you in modifying your setup to allow the script to run better behaved.
Next, consider only backing up the standby peer (letting your backup program determine which is active). Finally, you can increase the priority of the HAAst process by increasing the [common] processpriority value by 2 (or higher if that is not sufficient).
