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HA improves network reliability and helps carriers quickly deploy CGN devices on IPv4-
to-IPv6 networks.
l
Benefits to users
When a fault occurs on a service board, CGN device, or link, services are not interrupted,
and users do not even know the fault.
12.1.2 HA Backup Features
Warm Backup
HA supports warm backup in which mode user entries and address pool entry information are
backed up between the active and standby service boards and user sessions must be re-established
after active/standby switchover.
NOTE
By default, warm backup is enabled.
Hot Standby
HA supports hot standby in which mode user entries and address pool entry information are
backed up between the active and standby service boards, and user sessions are not interrupted
after active/standby switchover.
NOTE
To ensure uninterrupted sessions, hot standby is recommended. In the following HA backup introduction
and configuration, hot standby is used.
12.1.3 HA Backup Scenarios
HA backup can be configured between service boards on a single device or two devices.
Backup Between Service Boards on a Single CGN Device
When a CGN device has multiple service boards, active and standby service boards can be
configured on the CGN device for backup. The standby service board synchronizes data from
the active service board so that it can take over services immediately when the active service
board fails. Services are not interrupted during the switchover, and users do not know the fault.
NOTE
The active/standby status of the members in an HA backup group on a single CGN device is statically
configured.
As shown in the following figure, HA backup is configured between CPU0s on two service
boards of a CGN device.
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
12 CGN Backing Up HA Configuration
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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