Users Guide

BGP soft-reconguration clears the policies without resetting the TCP connection.
To reset a BGP connection using BGP soft reconguration, use the clear ip bgp command in EXEC Privilege mode at the
system prompt.
When you enable soft-reconguration for a neighbor and you execute the clear ip bgp soft in command, the update
database stored in the router is replayed and updates are reevaluated. With this command, the replay and update process is triggered
only if a route-refresh request is not negotiated with the peer. If the request is indeed negotiated (after execution of clear ip
bgp soft in), BGP sends a route-refresh request to the neighbor and receives all of the peer’s updates.
To use soft reconguration (or soft reset) without preconguration, both BGP peers must support the soft route refresh capability,
which is advertised in the open message sent when the peers establish a TCP session.
To determine whether a BGP router supports this capability, use the show ip bgp neighbors command. If a router supports
the route refresh capability, the following message displays: Received route refresh capability from peer.
If you specify a BGP peer group by using the peer-group-name argument, all members of the peer group inherit the
characteristic congured with this command.
• Clear all information or only specic details.
EXEC Privilege mode
clear ip bgp [vrf vrf-name] {* | neighbor-address | AS Numbers | ipv4 | peer-group-name}
[soft [in | out]]
– *: Clears all peers.
– neighbor-address: Clears the neighbor with this IP address.
– AS Numbers: Peers’ AS numbers to be cleared.
– ipv4: Clears information for the IPv4 address family.
– peer-group-name: Clears all members of the specied peer group.
• Enable soft-reconguration for the BGP neighbor specied.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} soft-reconfiguration inbound
BGP stores all the updates received by the neighbor but does not reset the peer-session.
Entering this command starts the storage of updates, which is required to do inbound soft reconguration. Outbound BGP soft
reconguration does not require inbound soft reconguration to be enabled.
Example of Soft-Recongration of a BGP Neighbor
The example enables inbound soft reconguration for the neighbor 10.108.1.1. All updates received from this neighbor are stored
unmodied, regardless of the inbound policy. When inbound soft reconguration is done later, the stored information is used to
generate a new set of inbound updates.
Dell>router bgp 100
neighbor 10.108.1.1 remote-as 200
neighbor 10.108.1.1 soft-reconfiguration inbound
Route Map Continue
The BGP route map continue feature, continue [sequence-number], (in ROUTE-MAP mode) allows movement from one
route-map entry to a specic route-map entry (the sequence number).
If you do not specify a sequence number, the continue feature moves to the next sequence number (also known as an “implied
continue”). If a match clause exists, the continue feature executes only after a successful match occurs. If there are no successful
matches, continue is ignored.
210
Border Gateway Protocol IPv4 (BGPv4)