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0/0/0<br />

192.168.17.1 65500 501 515 0 0 4:10:25 0/0/0<br />

0/0/0<br />

10.0.31.1 65505 181 182 0 3 1:27:46 4/8/1<br />

0/0/0<br />

The Damp State field in the first line shows that one route in the inet.0 routing table<br />

has been damped. Farther down in the output, you see that a connection to BGP<br />

peer 10.0.31.1 in AS 65505 is established because the State field shows that the<br />

router has received eight routes from that peer and four of them are active. The third<br />

number in the State field shows that one route is currently suppressed as a result of<br />

the damping policy.<br />

The show route damping command provides more information about damped<br />

routes. The suppressed detail option shows specific prefixes that are or have been<br />

suppressed:<br />

aviva@Router3> show route damping suppressed detail<br />

inet.0: 173318 destinations, 1533437 routes (172602 active, 11 holddown, 108105<br />

hidden)<br />

10.4.10.0/19 (1 entry, 0 announced)<br />

BGP /-101<br />

Next-hop reference count: 18064<br />

Source: 192.168.106.33<br />

Next hop: 192.168.106.33 via so-6/3/0.0, selected<br />

State: <br />

Local AS: 65000 Peer AS: 65530<br />

Age: 1:36<br />

Task: BGP_65530.192.168.106.33+179<br />

AS path: 65530 65531 65532 I ( )<br />

Communities: 65501:390 65501:2000 65501:3000 65504:6453<br />

Localpref: 100<br />

Router ID: 192.168.103.240<br />

Merit (last update/now): 12866/11594<br />

damping-parameters: damping-normal<br />

Last update: 00:01:36 First update: 1w3d 03:00:51<br />

Flaps: 13718<br />

Suppressed. Reusable in: 00:19:40<br />

Preference will be: 170<br />

Here, the prefix 10.4.10.0/19 is suppressed. While suppressed, the prefix is not<br />

active in the forwarding table, so there is no asterisk next to BGP on the second line of<br />

the output, and the prefix is hidden (noted in the State field) and is not exported to<br />

any BGP peers. The last several lines show the damping information. The dampingparameters<br />

line indicates that this route is being damped with the damping-normal<br />

parameters. The current figure-of-merit value is 11,594, which is above the reuse<br />

threshold of 3,000 that is set for damping-normal. The third line gives an idea of how<br />

long the prefix has been unusable. First update shows when the path attributes for<br />

the route were first changed (here, more than a week ago) and when they were last<br />

updated (about 1.5 hours ago). The next lines show that the route has flapped a total<br />

of 13,718 times. If the route remains stable and the path information for it does not<br />

462 | Chapter 13: BGP<br />

This is the Title of the Book, eMatter Edition<br />

Copyright © 2008 O’Reilly & Associates, Inc. All rights reserved.

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