Setup Guide

BGP router identifier 192.168.128.3, local AS number 100
BGP table version is 1, main routing table version 1
1 network entrie(s) using 132 bytes of memory
3 paths using 204 bytes of memory
BGP-RIB over all using 207 bytes of memory
2 BGP path attribute entrie(s) using 128 bytes of memory
2 BGP AS-PATH entrie(s) using 90 bytes of memory
2 neighbor(s) using 9216 bytes of memory
Neighbor AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/Pfx
192.168.128.1 99 93 99 1 0 (0) 00:00:15 1
192.168.128.2 99 122 120 1 0 (0) 00:00:11 1
Advanced BGP conguration tasks
The following sections describe how to congure the advanced (optional) BGP conguration tasks.
Route-refresh and Soft-reconguration
BGP soft-reconguration allows for faster and easier route changing.
Changing routing policies typically requires a reset of BGP sessions (the TCP connection) for the policies to take eect. Such resets cause
undue interruption to trac due to hard reset of the BGP cache and the time it takes to re-establish the session. BGP soft-reconguration
allows for policies to be applied to a session without clearing the BGP Session. Soft-reconguration can be done on a per-neighbor basis
and can either be inbound or outbound.
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 change the BGP inbound policy locally, you need to process the updates received from a peer. The route-refresh capability allows
the local peer to reset inbound information dynamically by exchanging route-refresh requests to supporting peers. When an inbound policy
conguration is changed, then the Dell EMC Networking OS sends a refresh request message asking the peer to re-advertise updates.
Upon receiving the refresh request, the peer advertises the required information after applying the outbound lters. Route-refresh is
negotiated during the BGP session establishment and will be used only if both the BGP peers support this capability.
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.
• Enable soft-reconguration for the BGP neighbor specied.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | ipv6-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.
• Reset BGP connection using soft-reconguration.
EXEC Privilege mode
clear ip bgp [vrf vrf-name] [* | neighbor-address | as-number | peer-group-name] {soft {in |
out}}
Border Gateway Protocol (BGP)
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