11.1 Interface Backup Troubleshooting
11.1.1 Interface Backup Fails to Take Effect
Common Causes
, RouterA and RouterB are connected.
Multiple interfaces on RouterA back up one another:
l
Interface1 is the primary interface.
l
Interface2 and interface3 are backup interfaces.
Figure 11-1
Networking diagram of interface backup
LAN2
LAN1
interface1
interface2
interface3
RouterA
RouterB
Interface backup cannot take effect in the following situations:
l
Backup interfaces become unavailable after the primary interface fails.
l
In load balancing mode, load balancing cannot be implemented among the primary and
backup interfaces because they cannot all be in Up state simultaneously.
l
In load balancing mode, traffic cannot be load balanced among multiple interfaces.
This fault is commonly caused by one of the following:
l
The physical status of backup interfaces is Down.
l
The link layer status of backup interfaces is Down.
l
In load balancing mode:
–
The load balancing threshold and maximum bandwidth are not configured for the
primary interface.
–
An equal-cost route is not generated.
–
Only one flow needs to be transmitted.
Troubleshooting Flowchart
shows the troubleshooting flowchart.
Huawei AR2200-S Series Enterprise Routers
Troubleshooting
11 Reliability
Issue 01 (2012-01-06)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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