Concept Guide

Capabilities advertised to neighbor for IPv4 Unicast :
MULTIPROTO_EXT(1)
ROUTE_REFRESH(2)
CISCO_ROUTE_REFRESH(128)
fall-over enabled
Update source set to Loopback 0
Peer active in peer-group outbound optimization
For address family: IPv4 Unicast
BGP table version 52, neighbor version 52
4 accepted prefixes consume 16 bytes
Prefix advertised 0, denied 0, withdrawn 0
Connections established 6; dropped 5
Last reset 00:19:37, due to Reset by peer
Notification History
'Connection Reset' Sent : 5 Recv: 0
Local host: 20.20.20.2, Local port: 65519
Foreign host: 10.10.10.1, Foreign port: 179
DellEMC#
To verify that fast fall-over is enabled on a peer-group, use the show ip bgp peer-group command (shown in bold).
DellEMC#sh ip bgp peer-group
Peer-group test
fall-over enabled
BGP version 4
Minimum time between advertisement runs is 5 seconds
For address family: IPv4 Unicast
BGP neighbor is test
Number of peers in this group 1
Peer-group members (* - outbound optimized):
10.10.10.1*
DellEMC#
router bgp 400
neighbor test peer-group
neighbor test
fall-over
neighbor test no shutdown
neighbor 10.10.10.1 remote-as 500
neighbor 10.10.10.1 fall-over
neighbor 10.10.10.1 update-source Loopback 0
neighbor 10.10.10.1 no shutdown
DellEMC#
Conguring Passive Peering
When you enable a peer-group, the software sends an OPEN message to initiate a TCP connection.
If you enable passive peering for the peer group, the software does not send an OPEN message, but it responds to an OPEN message.
When a BGP neighbor connection with authentication congured is rejected by a passive peer-group, Dell EMC Networking OS does not
allow another passive peer-group on the same subnet to connect with the BGP neighbor. To work around this, change the BGP
conguration or change the order of the peer group conguration.
Border Gateway Protocol (BGP)
209