the mPW between the UPE and the NPEs and forwarded by the mVSI. Other service packets
are transmitted through the service PW and exchanged by the service VSI between the UPE and
the NPEs.
Figure 8-2
Binding relation between the mVSI and the service VSI
PW for mVSI
PW for normal VSI
mVSI
VSI1
UPE
S9300
NPE2
NPE1
VSI2
VSI1 VSI2
VSI1 VSI2
The mVRRP packets and other service packets are transmitted through different PWs; therefore,
the packets are separated from each other.
The mVSI and the service VSI are bound on the UPE. When the VRRP group on the NPE
performs master/backup switchover, the following occurs:
1.
The mVSI on the UPE receives the gratuitous ARP packet sent from the NPE through the
mPW between the UPE and the NPEs.
2.
The mVSI checks whether the received gratuitous ARP packet is the same as the previously
received one. That is, the mVSI checks whether the two packets are received through the
same PW and whether their IP addresses, incoming labels, incoming interfaces, and MAC
addresses are the same.
l
If they are the same, it indicates that the mVRRP group between NPEs does not perform
the master/backup switchover.
l
If they are the different, it indicates that the mVRRP group between NPEs has performed
the master/backup switchover.
3.
The UPE clears the MAC addresses of all the bound service VSIs according to the binding
relation between the mVSI and the service VSI. In addition, the service VSI on the UPE
sends a MAC Withdraw message to all the peers in the local VSI. When receiving the
message, the remote peers clear the MAC addresses on the PW side.
4.
After the MAC address of the service VSI is cleared, the UPE broadcasts the received
packet destined for the new master NPE because the packet is an unknow frame. After
receiving the broadcast packets, the new master NPE learns the source MAC address of
the packet for the reverse traffic forwarding.
Quidway S7700 Smart Routing Switch
Configuration Guide - VPN
8 VPLS Convergence Configuration
Issue 01 (2011-07-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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