Resetting A Bgp Connection - Juniper BGP - CONFIGURATION GUIDE V 11.1.X Configuration Manual

JUNOSe 11.1.x BGP and MPLS Configuration Guide

Resetting a BGP Connection

When a routing policy changes, use the clear ip bgp and clear bgp ipv6 commands
to clear the current BGP session and implement the new policy.
Clearing a BGP session can create a major disruption in the network operation; this
is known as a hard clear. For this reason, you can use the soft in and soft out options
of the command (a soft clear) to activate policies without disrupting the BGP session.
The soft in option reapplies inbound policy to received routes; the soft out option
resends routes to a neighbor after reapplying outbound policy. The soft in prefix-list
option causes BGP to push any prefix list outbound route filters (ORFs) to the peer
and then reapply inbound policy to received routes.
NOTE: Resetting the BGP connection is slightly different when you change outbound
policies for peer groups for which you have enabled Adj-RIBs-Out. You cannot merely
perform a hard clear or outbound soft clear for individual peer group members
because that causes BGP to resend only the contents of the Adj-RIBs-Out table. If you
change the outbound policy for such a peer group and want to fill the Adj-RIBs-Out
table for that peer group with the results of the new policy, you must use the clear
ip bgp peer-group command to perform a hard clear or outbound soft clear of the
peer group.
clear bgp ipv6
clear ip bgp
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Configuring BGP Routing Policy
A route matches this community list only if it belongs to at least all three
communities in extended community list boston1: Communities 100:2, 100:3,
and 100:4.
Use the no version to remove a single extended community list entry if permit
or deny and a path-expression are specified. Otherwise, the entire community
list is removed.
See ip extcommunity-list.
Use to clear the current BGP connection or to activate a new policy without
clearing the BGP session.
You can specify the IP address of a BGP neighbor, the name of a BGP peer group,
or an address family to be cleared.
Use the asterisk (*) to clear all BGP connections.
If you do not use the soft in or soft out options, the clear is known as a hard
clear and clears the current BGP connection.
Use the soft in option to reapply inbound policy to all received routes without
clearing the BGP session.
Use the soft in prefix-filter option to push an ORF to the peer and reapply
inbound policy to all received routes without clearing the BGP session.