Optimization Of Switchover Control Outage Time; Configuring The Srp Context Interface Parameters - Cisco ASR 5000 Administration Manual

Interchassis Session Recovery
The require graceful-cleanup-during-audit-failure Global Configuration mode CLI command enables or
disables the graceful cleanup feature.
configure
require graceful-cleanup-during-audit-failure [ del-cause non-ims-apn { system-failure | none } ]

Optimization of Switchover Control Outage Time

The ICSR framework minimizes control outage time associated with the flushing of critical full checkpoint
statistics, network convergence and internal auditing.
The amount of time consumed by the following activities affects control outage time during switchover:
• Critical Flush – During the Active to Pending-Standby transition, all sessmgrs flush any pending critical
FCs (Full Checkpoints). During this time, the active chassis drops all control packets. If control signaling
is allowed during this stage, a call may get disconnected based on the control message type and accounting
information will be lost.
• Network Convergence – This encompasses the amount of time taken to update routes and send
control/data to the newly active chassis. Control messages are dropped during the transition.
• Accounting Flush – During this flush stage data counts are synchronized between chassis. If control
signaling is allowed during this flush, the call may get disconnected based on the control message type,
and accounting information will be lost for calls that existed before switchover.
• Audit – During audit new calls are not allowed because synchronization of call resources may result in
clearing of the calls.
The switchover control-outage-optimization CLI command allows new calls during the Accounting Flush,
as soon as the Audit is completed. This SRP Configuration mode command enables the quicker restoration
of control traffic (call-setup, modification, deletion) following an ICSR switchover.
configure
context context_name
service-redundancy-protocol
switchover control-outage-optimization
end

Configuring the SRP Context Interface Parameters

This procedure configures the communication interface with the IP address and port number within the SRP
context. This interface supports interchassis communication.
CLI commands must be executed on both chassis. Log onto both chassis before continuing. Always make
Important
configuration changes on the primary chassis first.
configure
context vpn_ctxt_name
interface srp_if_name
ip-address
exit
exit
port ethernet slot_num
description des_string
-noconfirm
[ ]
ip_address ip_address
{ |
port_num
/
ASR 5000 System Administration Guide, StarOS Release 21.1
Configuring the Service Redundancy Protocol (SRP) Context
mask
/ }
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