Phone Failover

When phone resilience is configured, the home system shares information about the registered phones and users on those phones with the backup system. If the home system is no longer visible to the phones, failover occurs and the phones register with the backup system.

Phone Failback

If the phone’s home system has been up for more than 10 minutes, the system causes idle phones to perform a failback to the home system. If the phone is unable to connect to the home system, there is a five minute grace period, referred to as homeless prevention, where the phone can be logged in to either the home or backup system.

Automatic failback to the home system is the default mode. Failback can be configured to operate manually. This may be desired if for example, the home system will be unavailable for some time. In manual mode, failback does not occur until the phone has been logged out or rebooted.

Notes on Phone Resiliency Behavior

• Failover handover takes a minimum of 3 minutes (longer for larger networks). This ensures that failover is not invoked when it is not required; for example, when the home system is simply being rebooted to complete a non-mergeable configuration change.

• Failover is only intended to provide basic call functionality while the cause of failover occurring is investigated and resolved. If users make changes to their settings while in failover, for example changing their DND mode, those changes will not apply after failback.  

• Calls anchored on the home system lose all voice paths during failover. Direct media calls in a stable state might maintain voice paths until the next call event, but this is not guaranteed.

• If the failover system is rebooted while it is providing failover services, the failover services are lost.

• Failover features require that the phones local to each system are still able to route data to the backup system when the home system is not available. This will typically require each system site to be using a separate data router.

• When an IP phone fails over, the backup system allows it to operate indefinitely as a “guest”, but only until the system resets. Licenses will never be consumed for a guest phone.

• Hot desking users are automatically logged out. When their base extension fails back to the home system, the user is automatically logged in on their base extension.

• The media security configuration should be the same on all systems. For example, if an extensions home system is set to Best Effort, the failover system should also be set to Best Effort.

• For secure communication using TLS/SRTP, all IP Office systems must have an identity certificate that has been signed by the same trusted root CA.

• Failover provides only basic call functionality for Avaya Workplace Client and call logs generated while connected to the backup server will not be available after failback.

• The primary and secondary servers should have the same configurations of Avaya cloud account authorization. If Avaya cloud account authorization is enabled on primary server and you have logged in with Avaya cloud account authorization, use the same login in secondary server during failover.

Supported Network Configurations

Phone resiliency is supported between any IP Office systems linked through an IP Office Line with Networking Level set to SCN. This includes failover from an IP500 V2 system to another IP500 V2 system.

For Server Edition deployments, failover from one node to any other node in the solution is supported.

Resiliency can be configured by specifying a Location with a unique IP address for the backup system.