Chassis As Mpls-Ce Connected To Asbr; Engineering Rules - Cisco ASR 5x00 Administration Manual

Multi-Protocol Label Switching (MPLS) Support
The CE does not run any MPLS protocol (LDP or RSVP-TE).
When receiving data packets in the downstream direction from the PE, the label is checked to identify the destination
VRF. Then the packet is de-encapsulated into an IP packet and sent to the session subsystem for processing.
Important:

Chassis as MPLS-CE Connected to ASBR

Figure 47.
The system in this scenario uses static/dynamic MPLS labels for ingress and egress traffic. For configuration
information on static label, refer to the
BGPMPLS VPN with Dynamic Labels
This scenario differs from the MPLS-CE with PE scenario in terms of peer functionality even though MPLS-CE
functionality does not change. Like the MPLS-CE with PE scenario, MPLS-CE system maintains VRF routes in various
VRFs and exchanges route information with peer over MP-eBGP session.
The peer in this scenario is not a PE router but an Autonomous System Border Router (ASBR). The ASBR does not
need to maintain any VRF configuration. The PE routers use IBGP to redistribute labeled VPN-IPv4 routes either to an
ASBR or to a route reflector (of which the ASBR is a client). The ASBR then uses the eBGP to redistribute those
labeled VPN-IPv4 routes to an MPLS-CE in another AS. Because of the eBGP connection, the ASBR changes the next-
hop and labels the routes learned from the iBGP peers before advertising to the MPLS-CE. The MPLS-CE is directly
connected to the eBGP peering and uses only the the MP-eBGP to advertise and learn routes. The MPLS-CE
pushes/pops a single label to/from the ASBR, which is learned over the MP-eBGP connection. This scenario avoids the
configuration of VRFs on the PE, which have already been configured on the MPLS-CE.

Engineering Rules

 Up to 250 virtual routing tables per context.
 Up to 5000 "host routes" spread across multiple VRFs per BGP process. Limited to 6000 pool routes per chassis.
 Up to 1024 VRFs per chassis.
MPLS ping/trace route debugging facilities are not supported.
Chassis as MPLS-CE Connected to ASBR
Configuring BGP/MPLS VPN with Static Labels
for dynamic lable configuration.
Cisco ASR 5x00 Packet Data Network Gateway Administration Guide ▄
Overview ▀
section and refer Configuring
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