Cisco CRS-1 - Carrier Routing System Router Troubleshooting Guide

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Cisco IOS XR Troubleshooting Guide for the Cisco CRS-1 Router
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Chapter 12 Multiprotocol Label Switching Checklist
Troubleshooting L3VPN MPLS Traffic Loss
• Determine how the problem state was encountered.
• Verify if the problem can be reproduced. If it can be reproduced, list the detailed steps to reproduce
the problem.
• Provide a decoded stack trace and core file for a process crash. Copy the core file to the applicable
TFTP location.
• Save the sample output from the show logging command to a file. Copy the file to the applicable
TFTP location. For more information, see Cisco IOS XR System Monitoring Command Reference
for the Cisco CRS-1 Router.
Troubleshooting L3VPN MPLS Traffic Loss
To troubleshoot the traffic loss of MPLS packets on L3VPN layer in Cisco CRS-1, perform the following
procedure. The general flow of packets in a Cisco CRS-1 goes through the following sequence:
Incoming interface => Ingress pse (the forwarding asic or mircocode) => Ingress queuing asic(xbma) =>
Switch fabric => Egress pse(forwarding asic or microcode) => Egress queuing asic(xbma) => Outgoing
interface.
For detailed steps, see Troubleshooting Transient Traffic Drop in Forwarding, page 3-88 in the
Troubleshooting Forwarding chapter.

Cisco CRS-1 - Carrier Routing System Router Specifications

General

Brand	Cisco
Model	CRS-1 - Carrier Routing System Router
Category	Network Router
Language	English