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Cisco ASR 9000 Series Aggregation Services Router Overview and Reference Guide
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High Availability and Redundant OperationThis chapter describes the high availability and redundancy features of the
Cisco ASR 9000 Series Routers.
Features Overview
The Cisco ASR 9000 Series Routers are designed to have high Mean Time Between Failures (MTBF)
and low Mean Time To Resolve (MTTR) rates, thus providing a reliable platform that minimizes outages
or downtime and maximizes availability.
In addition, the Cisco ASR 9000 Series Routers offer the following high availability (HA) features to
enhance network level resiliency and enable network-wide protection:
• High Availability Router Operations
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Stateful Switchover
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Fabric Switchover
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Non-Stop Forwarding
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Process Restartability
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Fault Detection and Management
• Power Supply Redundancy
• Cooling System Redundancy
High Availability Router Operations
The Cisco ASR 9000 Series Routers offer a variety of hardware and software high availability features.
Stateful Switchover
The RSP/RP cards are deployed in “active/standby” configurations. Stateful switchover (SSO) preserves
state and configuration information if a switchover to the standby RSP/RP card occurs. The standby
RSP/RP card has a mirror image of the state of protocols, users configuration, interface state, subscriber
state, system state and other parameters. Should a hardware or software failure occur in the active
RSP/RP card, the standby RSP/RP card changes state to become the active RSP/RP card. This stateful
switchover has no impact in forwarding traffic.