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Stinger® FS/Stinger FS+ Getting Started Guide
Configuring Control Modules and System Timing
Configuring control module redundancy
In the event of a control module switchover, the LIMs are not subject to a hardware
reset (to avoid the need to retrain the DSL modems). However, the system drops all
connections and rebuilds them after the new primary control module completes its
initialization. Log messages notify you of the following significant events related to
control module redundancy:
■
Control module becomes primary.
■
Control module became primary and no secondary is present.
■
Primary control module has lost heartbeat communication with the secondary
control module.
■
Primary control module has established heartbeat communication with the
secondary.
■
Control module has a software crash (Fatal log message).
Overview of the Redundancy profile settings
The Redundancy profile stores information, or
contexts
, that the two control modules
exchange within the heartbeat protocol to track each other’s status. The contexts are
stored as two arrays. The first array (context 1) represents the first control module
slot, and the second array (context 2) represents the second control module slot.
Most of the settings in the Redundancy profile are visible only when debug
permissions are enabled in the current User profile, and cannot be changed. But you
can modify the following Redundancy parameters, shown with default settings:
[in REDUNDANCY]
primary-preference = no-preference
[in REDUNDANCY:context[1]]
must-agree = False
[in REDUNDANCY:context[2]]
must-agree = False
Parameter
Setting
Primary-Preference
Control module that is given preference to become primary.
With the default
no-preference
setting, the decision is
left up to the system. The system chooses the controller
that was primary most recently, or the controller in slot 9.
If the parameter is set to
first-controller-preferred
, the system gives
preference to the controller in the first control module slot
(slot 8). If the control module in the first slot is not
available, the system designates the control module in the
second slot as primary.
If the parameter is set to
second-controller-preferred
, the system gives
preference to the controller in the second control module
slot (slot 9). If that control module is not available, the
system designates the control module in the first slot as
primary.
