HPE FlexNetwork 5510 HI Series, Руководство по настройке Mpls

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Figure 97 H-VPLS using Ethernet access
As shown in Figure 97 , in Ethernet access mode, the edge domain is an Ethernet network. The UPE
and NPE 1 establish a point-to-point Ethernet QinQ connection in between (enable QinQ on the UPE
interfaces connecting CEs and configure VLAN access mode on NPE 1). After UPE receives a
packet from a CE, it adds an outer VLAN tag into the packet and forwards the packet to NPE 1. NPE
1 regards the outer VLAN tag as the service provider VLAN tag. It maps the packet to the VSI that
corresponds to the VLAN tag and then searches the MAC address table of the VSI to forward the
packet.
UPE dual homing and PW redundancy
A single PW between a UPE and an NPE has a distinct drawback: once the PW fails, all customer
sites connected to the UPE lose connectivity. You can connect a UPE to two NPEs to achieve U-PW
redundancy.
In the H-VPLS using MPLS access as shown in Figure 98 , the UPE connects to two NPEs through
primary and backup U-PWs. The UPE uses the primary U-PW to forward traffic. When the primary
U-PW fails, the UPE uses the backup U-PW to forward traffic.
Figure 98 UPE dual homing and redundancy in H-VPLS using MPLS access
The backup U-PW is used in the following scenarios:
•
The tunnel that carries the primary U-PW is deleted after a fault detection mechanism such as
BFD detects a failure on the tunnel, which causes the primary U-PW to go down.
CE 3
NPE 3 NPE 1
N-PW
CE 1
CE 2
NPE 2
UPE
QinQ
N-PW N-PW
Backbone
domain
Edge domain
(Ethernet)
CE 1
NPE 3
NPE 1 NPE 2
CE 2
Backbone domain
N-PW
NPE 4
N-PW
N-PW N-PW
CE 3
CE 4
N-PW N-PW
UPE
Primary U-PW
Backup U-PW
Edge domain (MPLS)