Failed-Route Notification

T-Server supports a variety of alarm messages for unsuccessful routing scenarios.

When this feature is enable, a failed route timer is set using the interval defined in the route-failure-alarm-period configuration option. Each routing failure reported during this period is added to a counter. If this counter exceeds a high water mark threshold value defined by the route-failure-alarm-high-wm configuration option, T-Server sets a route failure alarm condition, and resets the counter.

The alarm condition is cleared when fewer route failures than what is configured in the route-failure-alarm-low-wm configuration option are recorded and, also, there is no more than the number of route failures configured in the route-failure-alarm-high-wm option in one complete period (configured in the route-failure-alarm-period option).

Setting the value of the route-failure-alarm-period option to 0 (zero) disables this feature.

HA Considerations

Only the primary T-Server maintains the failed routing counter. The backup T-Server does not run the route-failure-alarm-period option timer, so it keeps the routing failure alarm in the canceled state.

• On switchover from the primary role to the backup role, T-Server stops the route-failure-alarm-period option timer and clears any alarm internally, without sending any LMS message.

• On switchover from the backup role to the primary role, T-Server starts the route-failure-alarm-period option timer and starts counting routing requests and routing failures.