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Figure 1-4
Networking diagram of BFD for VRRP
Backbone
VRRP
BFD for VRRP
PE1
PE2
Switch1
Switch2
, PE1 and PE2 form a VRRP master and backup group, serving as the
backup for each other. The VRRP backup group monitors BFD session. For example, when PE1
serves as the primary PE and the link between Switch1 and PE1 fails, the failure is fast detected
through BFD and reported to VRRP. The VRRP master and backup group performs switchover
fast and then PE2 becomes the primary PE.
1.4.3 Failure on the Remote PE - VPN FRR
In VPN FRR(Fast ReRoute), BFD can detect connectivity faults between PEs.
Figure 1-5
Networking diagram of VPN FRR application
PE1
P1
P2
P3
PE2
PE3
PE4
P4
P5
P6
, PE3 and PE4 access the VPN. If the user network on the left of PE1
needs to communicate with the user network on the right of PE3, PE1 can access the user network
on the right through PE3 and PE4. In this case, PE3 and PE4 serve as the backup for each other,
through which PE1 sends packets. This is how VPN FRR works.
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
1 Reliability Overview
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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