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inet.0: 173319 destinations, 1533435 routes (172627 active, 2 holddown, 108105<br />

hidden)<br />

10.108.0.0/15 (3 entries, 1 announced)<br />

BGP /-101<br />

Next-hop reference count: 69058<br />

Source: 192.168.60.85<br />

Next hop: 192.168.60.85 via so-3/1/0.0, selected<br />

State: <br />

Inactive reason: Unusable path<br />

Local AS: 65000 Peer AS: 65220<br />

Age: 2d 22:48:10<br />

Task: BGP_65220.192.168.60.85+179<br />

AS path: 65220 65501 65502 I ( )<br />

Communities: 65501:390 65501:2000 65501:3000 65504:3561<br />

Localpref: 100<br />

Router ID: 192.168.80.25<br />

Merit (last update/now): 1000/932<br />

damping-parameters: set-normal<br />

Last update: 00:01:05 First update: 00:01:05<br />

Flaps: 1<br />

History entry. Expires in: 00:22:20<br />

This output is similar to the show route damping suppressed detail command. It also<br />

shows in the Inactive reason line that the path is hidden because it is unusable.<br />

Unusable path can mean one of three things: that the route was rejected as the result<br />

of an import routing policy, that the route has been damped (which is the case here),<br />

or that the next hop to the route cannot be resolved.<br />

Checking the routing table entries for 10.108.0.0/15 confirms that the route is<br />

unusable:<br />

aviva@Router3> show route 10.108.0.0/15 exact all<br />

inet.0: 173321 destinations, 1533468 routes (172617 active, 14 holddown, 108123<br />

hidden)<br />

+ = Active Route, - = Last Active, * = Both<br />

10.108.0.0/15 *[BGP/170] 02:59:16, localpref 120, from 172.24.250.123<br />

AS path: (64603) 65503 65503 65503 I<br />

> via so-2/0/0.0, label-switched-path 1<br />

via so-2/0/0.0, label-switched-path 2<br />

[BGP/170] 5w3d 11:43:01, localpref 100, from 172.24.20.129<br />

AS path: 65520 65521 I<br />

via so-1/2/0.0<br />

> via so-5/1/0.0<br />

via so-6/0/0.0<br />

[BGP ] 2d 22:49:33, localpref 100<br />

AS path: 65220 65501 65502 I<br />

> to 192.168.60.85 via so-3/1/0.0<br />

The third route to 10.108.0.0/15, using the SONET interface so-3/1/0.0, is the one<br />

that is suppressed. You can confirm this because no preference value is associated<br />

with the route. You see [BGP ] instead of [BGP/170].<br />

464 | 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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