Session Recovery; How Session Recovery Works - Cisco ASR 5500 System Administration Manual

Hide thumbs Also See for ASR 5500:
Table of Contents

Advertisement

Session Recovery

With robust hardware failover and redundancy protection, any hardware or software failures on the system
can quickly be corrected. However, software failures can occur for numerous reasons, often without prior
indication.
This chapter describes the Session Recovery feature that provides seamless failover and reconstruction of
subscriber session information in the event of a hardware or software fault.
Important
This chapter includes the following sections:

How Session Recovery Works

This section provides an overview of how this feature is implemented and the recovery process.
The Session Recovery feature provides seamless failover and reconstruction of subscriber session information
in the event of a hardware or software fault within the system preventing a fully connected user session from
being disconnected.
Session recovery is performed by mirroring key software processes (for example, session manager and AAA
manager) within the system. These mirrored processes remain in an idle state (standby-mode) wherein they
perform no processing, until they may be needed in the event of a software failure (for example, a session
manager task aborts).
There are some situations wherein session recovery may not operate properly. These include:
Session Recovery is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information
on installing and verifying licenses, refer to the Managing License Keys section of Software Management
Operations.
How Session Recovery Works, page 257
Configuring the System to Support Session Recovery, page 259
Recovery Control Task Statistics, page 263
C H A P T E R
ASR 5500 System Administration Guide, StarOS Release 21.5
24
257

Advertisement

Table of Contents
loading

Table of Contents