Allow All Data Traffic; Allow Early Active Transition; Graceful Cleanup Of Icsr After Audit Of Failed Calls - Cisco ASR 5500 System Administration Manual

Configuring the Service Redundancy Protocol (SRP) Context
service-redundancy-protocol
switchover allow-volte-data-traffic [ maintain-accounting ]
Notes:
• When maintain-accounting is enabled, accounting accuracy is maintained for VoLTE calls.VoLTE
data is allowed on the active gateway after VoLTE accounting statistics are flushed.

Allow All Data Traffic

The SRP Configuration mode switchover allow-all-data-traffic command allows all data traffic (VoLTE
and non-VoLTE) during switchover transition. This command overwrites the switchover
allow-volte-data-traffic command if enabled on a P-GW. This feature reduces data traffic outage during the
switchover.
Important This CLI command must be run on both the active and standby chassis to enable this feature.
All data traffic is allowed on the active chassis during flushing and internal auditing. The billing information
is reconciled in the background once the flush is complete.

Allow Early Active Transition

The SRP Configuration mode switchover allow-early-active-transition command enables early transition
to active state during an ICSR switchover. By default this feature is disabled.
Use this command in concert with the switchover allow-all-data-traffic or allow-volte-data-traffic (without
maintain accounting option) command to further reduce data outage during a planned switchover. The outage
window is the amount time between initiating an ICSR switchover and when the newly active chassis starts
processing data.
You must enable one of the commands identified above on both ICSR chassis prior to enabling this
Important
command.

Graceful Cleanup of ICSR After Audit of Failed Calls

During an Audit on the gateways (P-GW/S-GW/GGSN/SAE-GW) after Session Recovery or an ICSR event,
if any critical information, internally or externally related to a subscriber session seems inconsistent, ICSR
will locally purge the associated session information.
Since external gateways (peer nodes) are unaware of the purging of this session, the UE session may be
maintained at other nodes. This leads to hogging of resources external to the gateway and an unreachable UE
for VoLTE calls.
When this feature is enabled, graceful cleanup for an ICSR audit of failed calls occurs. External signaling
notifies peers of session termination before purging the session. The gateway will attempt to notify external
peers of the removal of the session. External nodes to the local gateway include S-GW, P-GW, SGSN, MME,
AAA, PCRF and IMSA.
Audit failure can occur because of missing or incomplete session information. Therefore, only the peers for
which the information is available will be notified.
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Interchassis Session Recovery