Mpls L3Vpn Frr - HP FlexNetwork 10500 Series Configuration Manual

However, the AS number substitution feature also introduces a routing loop in Site 2 because route
updates originated from CE 3 can be advertised back to Site 2 through PE 2 and CE 2. To remove
the routing loop, you can configure the same SoO attribute on PE 2 for CE 2 and CE 3. PE 2 adds the
SoO attribute to route updates received from CE 2 or CE 3, and checks the SoO attribute of route
updates to be advertised to CE 2 or CE 3. The SoO attribute of the route updates from CE 3 is the
same as the SoO attribute for CE 2, and PE 2 does not advertise route updates to CE 2.
For more information about the SoO attribute, see Layer 3—IP Routing Configuration Guide.

MPLS L3VPN FRR

MPLS L3VPN Fast Reroute (FRR) is applicable to a dual-homed scenario, as shown in
using BFD to detect the primary link, FRR enables a PE to use the backup link when the primary link
fails. The PE then selects a new optimal route, and uses the new optimal route to forward traffic.
MPLS L3VPN FRR supports the following types of backup:
•
VPNv4 route backup for a VPNv4 route.
•
VPNv4 route backup for an IPv4 route.
•
IPv4 route backup for a VPNv4 route.
VPNv4 route backup for a VPNv4 route
Figure 60 Network diagram
VPN 1
As shown in
VPN 1 as PE 3. When PE 1 receives a VPNv4 route to CE 2 from both PE 2 and PE 3, it uses the
route from PE 2 as the primary link, and the route from PE 3 as the backup link.
Configure BFD for LSPs or MPLS TE tunnels on PE 1 to detect the connectivity of the public tunnel
from PE 1 to PE 2. When the tunnel PE 1—PE 2 operates correctly, traffic from CE 1 to CE 2 goes
through the path CE 1—PE 1—PE 2—CE 2. When the tunnel fails, the traffic goes through the path
CE 1—PE 1—PE 3—CE 2.
In this scenario, PE 1 is responsible for primary link detection and traffic switchover.
For more information about BFD for LSPs or MPLS TE tunnels, see
PE 1
CE 1
Figure 60, configure FRR on the ingress node PE 1, and specify the backup next hop for
PE 2
MPLS
backbone
PE 3
199
Figure
VPN 1
CE 2
Primary link
Backup link
"Configuring MPLS OAM."
60. By