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y 13:31:06 the LSP was up and running and was selected as the active path. Consult<br />

the LSP’s log to help determine the causes of MPLS errors in the network.<br />

You may be wondering why RSVP is using CSPF when setting up the LSP when we<br />

haven’t included anything about turning on CSPF in the configuration. By default,<br />

JUNOS RSVP uses CSPF to calculate paths. The data that RSVP uses for the CSPF<br />

calculation comes from an IGP, either IS-IS or OSPF. Extensions to both protocols<br />

allow them to collect information about the network topology and available bandwidth<br />

on network links. The JUNOS implementations of both IGPs support the<br />

extensions. This network data for CSPF is stored in a TED on each router. In the<br />

JUNOS IS-IS software, these extensions are on by default. Because IS-IS is running as<br />

one of the IGPs in our network, it automatically carries the traffic-engineering information.<br />

Here’s how you can disable the IS-IS support for TE:<br />

[edit protocols isis]<br />

aviva@R1# set traffic-engineering disable<br />

In the JUNOS OSPF, the extensions are off by default. You must explicitly configure<br />

OSPF support of the CSPF computation:<br />

[edit protocols ospf]<br />

aviva@R1# set traffic-engineering<br />

Use the following command to see what information IS-IS and OSPF have added to<br />

the TED database:<br />

aviva@R1> show ted database<br />

TED database: 3 ISIS nodes 3 INET nodes<br />

ID<br />

Type Age(s) LnkIn LnkOut Protocol<br />

R1.00(10.0.0.1) Rtr 239 1 1 IS-IS(2)<br />

To: R3.00(10.0.0.3), Local: 10.1.13.1, Remote: 10.1.13.2<br />

ID<br />

Type Age(s) LnkIn LnkOut Protocol<br />

OSPF(0.0.0.0)<br />

To: R3.00(10.0.0.3), Local: 10.1.13.1, Remote: 10.1.13.2<br />

ID<br />

Type Age(s) LnkIn LnkOut Protocol<br />

R3.00(10.0.0.3) Rtr 468 2 2 IS-IS(2)<br />

To: R1.00(10.0.0.1), Local: 10.1.13.2, Remote: 10.1.13.1<br />

To: R6.00(10.0.0.6), Local: 10.1.36.1, Remote: 10.1.36.2<br />

ID<br />

Type Age(s) LnkIn LnkOut Protocol<br />

R6.00(10.0.0.6) Rtr 431 1 1 IS-IS(2)<br />

To: R3.00(10.0.0.3), Local: 10.1.36.2, Remote: 10.1.36.1<br />

This output shows three entries and that both IS-IS and OSPF are contributing to the<br />

TED database (listed in the Protocol column). All three entries were learned from<br />

routers (shown in the Type column). You see that R1 (the ingress router) has one link<br />

in and one link out, R2 (the transit router) has two links in either direction, and R3<br />

(the egress router) has one link in and one out, which matches the LSP. The To: lines<br />

show the router IDs that correspond to the three routers in the LSP.<br />

Setting Up RSVP-Signaled LSPs | 509<br />

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

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

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