Explicit Route: Bad Strict Route Event

LSP Event

Explicit route: bad strict route

Sample Output 1

user@R1> show mpls lsp extensive

[...Output truncated...]

   36 Jan  4 18:04:57 CSPF: link down/deleted 10.1.13.1(R1.00/10.0.0.1) 
->10.1.13.2(R3.00/10.0.0.3)

   35 Jan  4 18:04:57 CSPF failed: no route toward 10.0.0.6

   34 Jan  4 18:04:57 Clear Call

   33 Jan  4 18:04:57 Explicit Route: bad strict route

   32 Jan  4 18:04:57 No Route toward dest

   31 Jan  4 18:04:57 Down

[...Output truncated...]

Sample Output 2

user@host> show mpls lsp extensive

Ingress LSP: 34 sessions



10.172.2.99

From: 10.172.162.18, State: Up, ActiveRoute: 3726, LSPname:

dcr2.den_to_dcr1.chd_P

ActivePath: P1_dcr2.den_to_dcr1.chd (primary)

LoadBalance: Random

Metric: 25

Encoding type: Packet, Switching type: Packet, GPID: IPv4

*Primary P1_dcr2.den_to_dcr1.chd State: Up

Received RRO (ProtectionFlag 1=Available 2=InUse 4=B/W 8=Node

10=SoftPreempt):

10.70.192.134

16 Jun 28 18:27:51 Selected as active path

15 Jun 28 18:27:51 Record Route: 10.70.192.134

14 Jun 28 18:27:51 Up

13 Jun 28 18:27:29 Deselected as active

12 Jun 28 18:27:28 No Route toward dest

11 Jun 28 18:27:28 Down

10 Jun 18 03:52:18 Selected as active path

9 Jun 18 03:52:18 Record Route: 10.70.192.134

8 Jun 18 03:52:18 Up

7 Jun 18 03:52:18 Originate Call

6 Jun 18 03:52:18 Clear Call

5 Jun 18 03:52:18 Deselected as active

4 Jun 18 02:56:25 Selected as active path

3 Jun 18 02:56:25 Record Route: 10.70.192.134

2 Jun 18 02:56:25 Up

1 Jun 18 02:56:25 Originate Call

Standby B1_dcr2.den_to_dcr1.chd State: Dn

18 Jun 29 12:49:21 10.70.192.26: Routing loop detected[4798 times]

17 Jun 27 00:53:42 10.70.192.77: Explicit Route: bad strict route[20 times]

16 Jun 27 00:39:49 204.70.192.26: Routing loop detected [3370 times]

[...Output truncated...]

What It Means

This LSP event indicates that a poorly formed ERO was generated. Sample Outputs 1 and 2 show that this LSP event was caused by different situations described below.

Cause

This LSP event can be caused by several factors:

• A strict hop address specified for an LSP on a link that does not have RSVP enabled.
• The no-cspf statement included in the LSP configuration.
• An error with the configuration of constraints on a Constrained Shortest Path First (CSPF) LSP generates the CSPF: No route towards dest message, followed by the Explicit Route: bad strict route event.
• An ERO that causes a routing loop. See Sample Output 2.

Action

Examine the strict hop address, remove the no-cspf statement, or examine the path and verify that RSVP is enabled on each interface.