Cisco NCS 5500 Series

Update group for IPv4 Unicast, index 0.2:
Attributes:
Minimum advertisement interval:30
Messages formatted:2, replicated:2
Neighbors in this update group:
10.0.101.91
L3VPN iBGP PE-CE
The L3VPN iBGP PE-CE feature helps establish an iBGP (internal Border Gateway Protocol) session between
the provider edge (PE) and customer edge (CE) devices to exchange BGP routing information. A BGP session
between two BGP peers is said to be an iBGP session if the BGP peers are in the same autonomous systems.
Restrictions for L3VPN iBGP PE-CE
The following restrictions apply to configuring L3VPN iBGP PE-CE:
•
When the iBGP PE CE feature is toggled and the neighbor no longer supports route-refresh or
soft-reconfiguration inbound, a manual session flap must be done to see the change. When this occurs,
the following message is displayed:
RP/0/0/CPU0: %ROUTING-BGP-5-CFG_CHG_RESET: Internal VPN client configuration change on
neighbor 10.10.10.1 requires HARD reset
(clear bgp 10.10.10.1) to take effect.
•
iBGP PE CE CLI configuration is not available for peers under default-VRF, except for
neighbor/session-group.
•
This feature does not work on regular VPN clients (eBGP VPN clients).
•
Attributes packed inside the ATTR_SET reflects changes made by the inbound route-policy on the iBGP
CE and does not reflect the changes made by the export route-policy for the specified VRF.
•
Different VRFs of the same VPN (that is, in different PE routers) that are configured with iBGP PE-CE
peering sessions must use different Route Distinguisher (RD) values under respective VRFs. The iBGP
PE CE feature does ot work if the RD values are the same for the ingress and egress VRF.
Configuring L3VPN iBGP PE-CE
L3VPN iBGP PE-CE can be enabled on the neighbor, neighbor-group, or session-group. To configure L3VPN
iBGP PE-CE, follow these steps:
Before You Begin
The CE must be an internal BGP peer.
BGP Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.2.x
60
Implementing BGP
L3VPN iBGP PE-CE