Cisco ASR 5000 Series, Обзор продукта

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Enhanced Charging Service Overview
▀ Redundancy Support in ECS
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
On failure of an active chassis:
On system startup, xDR files are generated in accordance with the standard processes and formats. If the
system fails at any time it results in an inter-chassis session recovery switchover from active to standby and the
following occurs depending on the state of the call/flow records and xDR file at the time of failure:
Call/flow records that were being generated and collected in system memory prior to being written out
to /records directory on packet processing card RAM are not recoverable and therefore are lost.
Closed xDRs that have been written out to records directory on packet processing card RAM but that
have yet to be retrieved by the ESS are recoverable.
Closed xDRs that have been retrieved and processed by the ESS have no impact.
On the activation of a Standby chassis:
Upon detection of a failure of the original active chassis, the standby chassis transits to the active state and
begins serving the subscriber sessions that were being served by the now failed chassis. Any subsequent new
subscriber session will be processed by this active chassis and will generate xDRs per the standard processes
and procedures.
However, this transition impacts the xDRs for those subscribers that are in-progress at the time of the
transition. For in progress subscribers, a subset of the xDR fields and their contents are carried over to the
newly active chassis via the SRP link. These fields and their contents, which are carried over after an Inter-
chassis Session Recovery switchover, are as follows:
HA-CORRELATION-ID
PDSN-CORRELATION-ID (PDSN only)
PDSN-NAS-IP-ADDRESS (PDSN only)
PDSN-NAS-ID (PDSN only)
USERNAME
MSID
RADIUS-NAS-IP-ADDRESS
All remaining fields are populated in accordance with the procedures associated with any new flow with the
exceptions that, the field ―First Packet Direction‖ is set to ―Unknown‖ for all in-progress flows that were
interrupted by the switchover and the field ―FDR Reason‖ is marked as a PDSN Handoff and therefore is set to
a value of ―1‖ and corresponding actions are taken by the billing system to assure a proper and correct
accounting of subscriber activities.