Concept Guide

DellEMC(conf-router_bgp)# neighbor 10.108.1.1 soft-reconfiguration inbound
DellEMC(conf-router_bgp)# exit
Route-refresh
This section explains how the soft-reconguration and route-refresh works. Soft-reconguration has to be congured explicitly for a
neighbor unlike route refresh, which is automatically negotiated between BGP peers when establishing a peer session.
The route-refresh updates will be sent, only if the neighbor soft-reconfiguration inbound command is not congured in a
BGP neighbor and when you do a soft reset using clear ip bgp {neighbor-address | peer-group-name} soft in
command.
If the neighbor soft-reconfiguration inbound command is already congured in the BGP neighbor, the route refresh updates
will not be sent. If you want to use route-refresh updates instead, remove the neighbor soft-reconfiguration inbound
conguration and do a hard reset once, using clear ip bgp {* | as-number | ipv4| ipv6 | neighbor-address |
peer-group-name} command. If you remove neighbor soft-reconfiguration inbound conguration for an individual
neighbor (not part of peer-group), it is sucient to do a hard reset only for the individual neighbor. If the neighbor is part of a peer-group
and when neighbor soft-reconfiguration inbound is removed from the peer group, you need to do a hard reset for the peer-
group.
If neighbor soft-reconfiguration inbound command is not congured ever in the router, then doing a soft reset is enough for
the route-refresh updates to be sent.
Route-refresh updates for IPv4 and IPv6 prexes
This section explains the route-refresh functionality in dierent combinations for IPv4 or IPv6 prex congured with IPv4 or IPv6
neighbors.
By default, the IPv4 prexes is sent for all the neighbors irrespective of IPv4 address family is enabled or disabled. Following are the
dierent scenarios during which the route-refresh message is sent for the corresponding neighbors:
By default, the route-refresh message for IPv4 prexes is sent for both the IPv4 and IPv6 neighbors. Following is an example conguration
in which IPv4 prexes are enabled by default and the corresponding route-refresh message:
DellEMC(conf-router_bgp)# show config
!
router bgp 100
redistribute connected
neighbor 20.1.1.2 remote-as 200
neighbor 20.1.1.2 no shutdown
neighbor 20::2 remote-as 200
neighbor 20::2 no shutdown
!
address-family ipv6 unicast
redistribute connected
exit-address-family
!
DellEMC(conf-router_bgp)#do clear ip bgp 20.1.1.2 soft in
May 8 15:28:11 : BGP: 20.1.1.2 sending ROUTE_REFRESH AFI/SAFI (1/1)
May 8 15:28:12 : BGP: 20.1.1.2 UPDATE rcvd packet len 56
May 8 15:28:12 : BGP: 20.1.1.2 rcvd UPDATE w/ attr: origin ?, path 200, nexthop 20.1.1.2,
metric 0,
<output truncated>
DellEMC(conf-router_bgp)#do clear ip bgp 20::2 soft in
May 8 15:28:04 : BGP: 20::2 sending
ROUTE_REFRESH AFI/SAFI (1/1)
May 8 15:28:04 : BGP: 20::2 UPDATE rcvd packet len 56
May 8 15:28:04 : BGP: 20::2 rcvd UPDATE w/ attr: origin ?, path 200, nexthop 20.1.1.2, metric
0,
<output truncated>
Border Gateway Protocol (BGP)
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