Closing or resetting a neighbor session – Brocade FastIron Ethernet Switch Layer 3 Routing Configuration Guide User Manual

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Notification Sent: Unspecified

Notification Received: Unspecified

TCP Connection state: ESTABLISHED

Byte Sent: 115, Received: 492

Local host: 10.4.0.1, Local Port: 179

Remote host: 10.4.0.2, Remote Port: 8053

ISentSeq: 52837276 SendNext: 52837392 TotUnAck: 0

TotSent: 116 ReTrans: 0 UnAckSeq: 52837392

IRcvSeq: 2155052043 RcvNext: 2155052536 SendWnd: 16384

TotalRcv: 493 DupliRcv: 0 RcvWnd: 16384

SendQue: 0 RcvQue: 0 CngstWnd: 1460

Closing or resetting a neighbor session

You can close a neighbor session or resend route updates to a neighbor.

If you make changes to filters or route maps and the neighbor does not support dynamic route refresh,
use the following methods to ensure that neighbors contain only the routes you want them to contain:

• If you close a neighbor session, the device and the neighbor clear all the routes they learned from

each other. When the device and neighbor establish a new BGP4 session, they exchange route
tables again. Use this method if you want the device to relearn routes from the neighbor and resend
its own route table to the neighbor.

• If you use the soft-outbound option, the device compiles a list of all the routes it would normally

send to the neighbor at the beginning of a session. However, before sending the updates, the
device also applies the filters and route maps you have configured to the list of routes. If the filters
or route maps result in changes to the list of routes, the device sends updates to advertise, change,
or even withdraw routes on the neighbor as needed. This ensures that the neighbor receives only
the routes you want it to contain. Even if the neighbor already contains a route learned from the
device that you later decided to filter out, using the soft-outbound option removes that route from
the neighbor.

You can specify a single neighbor or a peer group.

To close a neighbor session and thus flush all the routes exchanged by the device and the neighbor,
enter the following command.

device# clear ip bgp neighbor all

The all , ip-addr , peer-group-name , and as-num parameters specify the neighbor. The ip-addr
parameter specifies a neighbor by its IP interface with the device. The peer-group-name specifies all
neighbors in a specific peer group. The as-num parameter specifies all neighbors within an AS and
has a range of 1 through 4294967295. The all keyword specifies all neighbors.

To resend routes to a neighbor without closing the neighbor session, enter a command such as the
following.

device# clear ip bgp neighbor 10.0.0.1 soft out

Clearing and resetting BGP4 routes in the IP route table

To clear BGP4 routes from the IP route table and reset the routes, enter a command such as the
following.

device# clear ip bgp routes

Syntax: clear ip bgp routes [ ip-addr/prefix-length ]

Closing or resetting a neighbor session

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FastIron Ethernet Switch Layer 3 Routing Configuration Guide

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