Troubleshooting guide

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Cisco PGW 2200 Softswitch Release 9.8 Operations, Maintenance, and Troubleshooting Guide
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Chapter 3 Cisco PGW 2200 Softswitch Platform Operations
Regular Operations
Caution The next step forces a manual switchover to the standby Cisco PGW 2200 Softswitch. Ensure that the
standby Cisco PGW 2200 Softswitch is fully operational and that debugging is turned off before taking
the active Cisco PGW 2200 Softswitch OOS, or there might be a total interruption of service.
A switchover can also cause call processing to fail if debugging is turned on.
Step 7 Log in to the active Cisco PGW 2200 Softswitch, start an MML session, and enter the following
command:
sw-over::confirm
Caution Switchover operations cause the loss of all SS7 messages that are transmitted to the Cisco PGW 2200
Softswitch for approximately 3 seconds. The loss of messages affects unstable in-progress calls as well
as new calls. Stable in-progress calls are not affected.
Site alarms are automatically set until the OOS Cisco PGW 2200 Softswitch is returned to an IS state.
Step 8 Verify that the switchover completed successfully. To verify a switchover, follow the procedure that is
described in the “Verifying Successful Completion of a Switchover” section on page 3-97.
Verifying Successful Completion of a Switchover
Determine whether a switchover (automatic or manual)is completed successfully by retrieving the status
of each Cisco PGW 2200 Softswitch. When all of the processes are active (the time that is required for
all processes to start depends on the amount of traffic), determine the platform state of both Cisco PGW
2200 Softswitches, as described in the “Verifying the Platform State of the Cisco PGW 2200
Softswitches” section on page 3-2. If the platform state of both Cisco PGW 2200 Softswitches is as
expected, the switchover is completed successfully. If one of the Cisco PGW 2200 Softswitches does not
return the expected platform state, the switchover did not complete successfully. See the “Recovering
from a Switchover Failure” section on page 6-170.
Understanding Switchover
Configure Cisco PGW 2200 Softswitches in an Active-Standby mode. In this mode, one Cisco PGW
2200 Softswitch runs active traffic while checkpointing information to the standby Cisco PGW 2200
Softswitch. In a continuous service configuration, the active Cisco PGW 2200 Softswitch is paired with
an identical standby Cisco PGW 2200 Softswitch that automatically takes over if a failure or switchover
occurs. The continuous service architecture of the Cisco PGW 2200 Softswitch increases the reliability,
availability, and failure-aversion capabilities of the system.
The primary goal of the Cisco PGW 2200 Softswitch switchover subsystem is to preserve calls if a
system fails. At any given time, one Cisco PGW 2200 Softswitch should be active while the other Cisco
PGW 2200 Softswitch is in a standby role. The active Cisco PGW 2200 Softswitch carries out the call
control function and updates the standby Cisco PGW 2200 Softswitch about call-processing events. The
standby Cisco PGW 2200 Softswitch maintains the same system state (in regard to call-processing) as
the active Cisco PGW 2200 Softswitch. In response to a critical failure on the active Cisco PGW 2200
Softswitch, the standby switches to the active role and takes over the call control function. There is a
period of approximately 3 seconds in which all messaging is lost in the process of switching over call
control.