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Configuration • 1:1 Chassis Redundancy Overview
APEX1000 All-Purpose Edge QAM Software Version 2.4.x • Installation and Operation Manual
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573408-001-a
1:1 Chassis Redundancy Overview
Starting with APEX firmware release version 2.1, the APEX1000/REM1000 RF
redundancy pair provides support for
narrowcast
content delivery. Firmware release
version 2.4.x offers a solution for
broadcast
content delivery. This option employs a
chassis redundancy design where a
secondary
APEX backs up a
primary
APEX, and
where each unit is capable of acting as either the
active
or the
standby
.
Please note the following system characteristics:
•
The APEXs autonomously failover when a fault is detected on the active APEX
•
Switchback from the standby APEX to the active APEX is manual
•
Encryption keys and ECMs are unique between APEXs in a redundancy pair
•
The primary and secondary APEXs use discrete PID spaces to prevent cross
streaming following a failover
•
Configuration is synchronized between the APEXs in the redundancy pair
Redundancy with Heartbeat
The APEXs communicate by means of a simple heartbeat message, continually
informing each other of their current state, role, and configuration. On cold reboot or
power cycling, both APEXs boot to a
standby
state; each then determines the correct
state into which it will transition. (Typically, the primary APEX enters the
active
state and
the secondary APEX enters the
standby
state.)
The primary and secondary APEXs use the heartbeat to synchronize their configurations.
Both APEXs receive encryption information from the DAC’s RDS interface and, if so
configured, both APEXs join the same multicast routes. In this scenario, both APEXs
generate PIDs, ECMs, and EMMs, but the secondary APEX has its RF ports muted.
When the secondary APEX recognizes that the primary APEX has failed (or is in a fault
state), it transitions to the active state and un-mutes its RF ports.
Note: This feature does not un-mute QAM channels that were explicitly muted by the
operator using the EM (when transitioning to the active state).