Reference Guide

● To add an IBGP neighbor, configure the as-number parameter with the same BGP as-number configured in the
router bgp as-number command.
6. (Optional) Add a text description for the template in ROUTER-TEMPLATE mode.
description text
7. Assign a peer-template with a peer-group name from which to inherit to the neighbor in ROUTER-NEIGHBOR mode.
inherit template template-name
8. Enable the neighbor in ROUTER-BGP mode.
neighbor ip-address
9. Enable the peer-group in ROUTER-NEIGHBOR mode.
no shutdown
When you add a peer to a peer group, it inherits all the peer group configured parameters. When you disable a peer group, all the
peers within the peer template that are in the Established state move to the Idle state. A neighbor cannot become a part of a
peer group if it has any of these commands configured:
● advertisement-interval
● next-hop-self
● route-map out
● route-reflector-client
● send-community
A neighbor may keep its configuration after it is added to a peer group if the neighbor configuration is more specific than the
peer group and if the neighbor configuration does not affect outgoing updates.
To display the peer-group configuration assigned to a BGP neighbor, enter the show ip bgp peer-group peer-group-
name command. The show ip bgp neighbor command output does not display peer-group configurations.
Configure peer templates
OS10(config)# router bgp 300
OS10(config-router-bgp-300) vrf blue
OS10(config-router-vrf)# template ebgppg
OS10(config-router-template)# remote-as 100
OS10(config-router-template)# description peer_template_1_abcd
OS10(config-router-template)# exit
OS10(config-router-vrf)# neighbor 3.1.1.1
OS10(config-router-neighbor)# inherit template ebgppg
OS10(config-router-neighbor)# no shutdown
Neighbor fall-over
The BGP neighbor fall-over feature reduces the convergence time while maintaining stability. When you enable fall-over, BGP
tracks IP reachability to the peer remote address and the peer local address.
When remote or peer local addresses become unreachable, BGP brings the session down with the peer. For example, if no
active route exists in the routing table for peer IPv6 destinations/local address, BGP brings the session down.
By default, the hold time governs a BGP session. Configure BGP fast fall-over on a per-neighbor or peer-group basis. BGP
routers typically carry large routing tables as frequent session resets are not desirable. If fail-over is enabled, the connection to
an internal BGP peer is immediately reset if the host route added to reach the internal peer fails.
1. Enter the neighbor IP address in ROUTER-BGP mode.
neighbor ip-address
2. Disable fast fall-over in ROUTER-NEIGHBOR mode.
no fall-over
Layer 3
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