HPE FlexNetwork 5510 HI Series, Руководство по настройке Mpls

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HoVPN supports HoPE recursion:
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An HoPE can act as a UPE to form a new HoPE with an SPE.
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An HoPE can act as an SPE to form a new HoPE with multiple UPEs.
HoVPN supports multilevel recursion. In HoPE recursion, the concepts of SPE and UPE are relative.
A PE might be the SPE of its underlayer PEs and a UPE of its SPE at the same time.
Figure 54 Recursion of HoPEs
Figure 54 shows a three-level HoPE. The PE in the middle is called the middle-level PE (MPE).
MP-BGP runs between SPE and MPE, and between MPE and UPE.
MP-BGP advertises the following routes:
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All the VPN routes of UPEs to the SPEs.
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The default routes of the VPN instance of the SPEs or the VPN routes permitted by the routing
policies to the UPEs.
The SPE maintains the VPN routes of all sites in the HoVPN. Each UPE maintains only VPN routes
of its directly connected sites. An MPE has fewer routes than the SPE but has more routes than a
UPE.
OSPF VPN extension
This section describes the OSPF VPN extension. For more information about OSPF, see Layer
3—IP Routing Configuration Guide .
OSPF for VPNs on a PE
If OSPF runs between a CE and a PE to exchange VPN routes, the PE must support multiple OSPF
instances to create independent routing tables for VPN instances. Each OSPF process is bound to a
VPN instance. Routes learned by an OSPF process are added into the routing table of the bound
VPN instance.
OSPF area configuration between a PE and a CE
The OSPF area between a PE and a CE can be either a non-backbone area or a backbone area.
In the OSPF VPN extension application, the MPLS VPN backbone is considered the backbone area
(area 0). The area 0 of each VPN site must be connected to the MPLS VPN backbone (physically
connected or logically connected through a virtual link) because OSPF requires that the backbone
area be contiguous.
BGP/OSPF interaction
If OSPF runs between PEs and CEs, each PE redistributes BGP routes to OSPF and advertises the
routes to CEs through OSPF. OSPF considers the routes redistributed from BGP as external routes
SPE
MPE
UPE
UPE
UPE
CE
CE
CE CE