Cisco Catalyst 3560-X Series, Руководство по настройке программного обеспечения

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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-25303-03
Chapter 1 Configuring IP Unicast Routing
Configuring Multi-VRF CE
To configure VRF, you create a VRF table and specify the Layer 3 interface associated with the VRF.
Then configure the routing protocols in the VPN and between the CE and the PE. BGP is the preferred
routing protocol used to distribute VPN routing information across the provider’s backbone. The
multi-VRF CE network has three major components:
• VPN route target communities—lists of all other members of a VPN community. You need to
configure VPN route targets for each VPN community member.
•
Multiprotocol BGP peering of VPN community PE routers—propagates VRF reachability
information to all members of a VPN community. You need to configure BGP peering in all PE
routers within a VPN community.
• VPN forwarding—transports all traffic between all VPN community members across a VPN
service-provider network.
Default Multi-VRF CE Configuration
Multi-VRF CE Configuration Guidelines
Note To use multi-VRF CE, you must have the IP services or advanced IP services feature set enabled on your
switch.
• A switch with multi-VRF CE is shared by multiple customers, and each customer has its own routing
table.
•
Because customers use different VRF tables, the same IP addresses can be reused. Overlapped IP
addresses are allowed in different VPNs.
•
Multi-VRF CE lets multiple customers share the same physical link between the PE and the CE.
Trunk ports with multiple VLANs separate packets among customers. Each customer has its own
VLAN.
•
Multi-VRF CE does not support all MPLS-VRF functionality. It does not support label exchange,
LDP adjacency, or labeled packets.
• For the PE router, there is no difference between using multi-VRF CE or using multiple CEs. In
Figure 1-6 , multiple virtual Layer 3 interfaces are connected to the multi-VRF CE device.
•
The switch supports configuring VRF by using physical ports, VLAN SVIs, or a combination of
both. The SVIs can be connected through an access port or a trunk port.
Table 1-14 Default VRF Configuration
Feature Default Setting
VRF Disabled. No VRFs are defined.
Maps No import maps, export maps, or route maps are defined.
VRF maximum routes Fast Ethernet switches: 8000
Gigabit Ethernet switches: 12000.
Forwarding table The default for an interface is the global routing table.