Network Router User Manual

Chapter 12
Troubleshooting Hardware Components
This chapter describes how to troubleshoot problems with hardware components
installed in the router. If you encounter software problems, or problems with hardware
components not discussed here, contact the Juniper Networks Technical Assistance
Center (JTAC) as described in “Requesting Support” on page xxiv.
■ Overview of Troubleshooting Resources on page 79
■ Troubleshooting the CFEB on page 83
■ Troubleshooting the Fan Tray on page 84
■ Troubleshooting PICs on page 84
■ Troubleshooting the Power System on page 85
Overview of Troubleshooting Resources
This section provides an overview of the resources you can use while troubleshooting
problems with the router:
■ Command-Line Interface on page 79
■ LEDs on page 80
■ Hardware and Interface Alarm Messages on page 80
■ Juniper Networks Technical Assistance Center on page 83
Command-Line Interface
The JUNOS Internet software command-line interface (CLI) is the primary tool for
controlling and troubleshooting router hardware, the JUNOS Internet software, routing
protocols, and network connectivity. CLI commands display information from routing
tables, information specific to routing protocols, and information about network
connectivity derived from the ping and traceroute utilities.
You enter CLI commands on one or more external management devices connected
to the Routing Engine through ports on the Routing Engine. The port labeled
AUX/MODEM attaches the Routing Engine to a laptop, modem, or other auxiliary
device, the port labeled CONSOLE attaches to a system console, and the port labeled
MGMT attaches to a management LAN. For more information, see “Routing Engine
Interface Ports” on page 16.
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