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Controlled Line Card Switchover Feature

SwitchManager provides the ability to configure line card redundancy. Once configured, SwitchManager will initiate a line card switchover whenever necessary.

By default SwitchManager forces the switchback from the N+1 card as soon as the failed card is available and no calls are presently active through LLC on the N+1 line card. If your call processing is switch resident, LLC will not know calls are active, and the switchback will happen immediately, potentially resulting in lost calls.

With the SK_SwitchBackFromStandbyConfig message the switchback from the redundant line card to the primary card becomes configurable.

The two message SK_SwitchBackFromStandbyConfig and SK_SwitchBackFromStandby allow you to perform a controlled switchover in a N+1 line card redundancy setup. In case a line card was out of service and comes back online, you can control when and how the primary card gets back into service.

Arguments

The following table shows the user modifiable arguments. Note that the action argument has different tasks in the messages: SwitchBackFromStandbyConfig and SwitchBackFromStandby.

:

Argument | Description
--- | ---
Action | In SK_SwitchBackFromStandbyConfig the action field can be set to: 0 = default behavior, perform the switchback when LLC determines the card is not handling any calls. 1 = perform switchback only after receiving the SwitchBackFromStandby message through the Converged Services Administrator (CSA) or other host application. In SK_SwitchBackFromStandby the action field can be set to: 0 = graceful switchback after LLC determines that the standby card is not handling any calls. 1 = forced switchback immediately.
Node | Specifies the node where the switchback is supposed to happen.
StandbySlot | Specifies the standby slot of the redundant card.

Return Values

The following table shows the possible return values for the switchback messages:

If the return value is | then...
--- | ---
SK_SUCCESS (0x10) | the switchback was successful.
SK_SWITCHBACK_FAILED (0xf00b) | the switchback failed, refer to the alarm.log for further detail.

Notation that describes line card redundancy, where N is the number of installed line cards of a single card type and 1 is an additional line card of that type designated as a standby card. For example, if you have three T-ONE cards and one additional standby T-ONE card installed, the system provides redundancy by activating the standby card if any of the three active T-ONE cards fail.
CSA. GUI-based tool used to configure, provision and monitor a Excel platform related to, for example, SIP, H.323, and VDAC Resouce Attributes.
See Converged Services Administrator.