Administrator Guide
– as-number: Clears the peers AS numbers.
– ipv4: Clears information for the IPv4 address family.
– ipv6: Clears information for the IPv6 address family.
– peer-group-name: Clears all members of the specied peer group.
– dampening: Clears all the ap dampening information.
– flap-statistics: Clears the ap statistics information.
Example of Soft-Recongration of a BGP Neighbor
The example enables inbound soft reconguration for the neighbor 10.108.1.1. All updates received from this neighbor are stored unmodied,
regardless of the inbound policy. When inbound soft reconguration is done later, the stored information is used to generate a new set of
inbound updates
DellEMC(conf)# router bgp 100
DellEMC(conf-router_bgp)# neighbor 10.108.1.1 remote-as 20
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-reconguration and route-refresh works. Soft-reconguration has to be congured 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 congured 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 congured 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
conguration 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 conguration for an individual
neighbor (not part of peer-group), it is sucient 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 congured 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 prexes
This section explains the route-refresh functionality in dierent combinations for IPv4 or IPv6 prex congured with IPv4 or IPv6
neighbors.
By default, the IPv4 prexes is sent for all the neighbors irrespective of IPv4 address family is enabled or disabled. Following are the
dierent scenarios during which the route-refresh message is sent for the corresponding neighbors:
By default, the route-refresh message for IPv4 prexes is sent for both the IPv4 and IPv6 neighbors. Following is an example conguration
in which IPv4 prexes 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
Border Gateway Protocol (BGP)
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