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Command-Line Interface

The Junos OS command-line interface (CLI) is the primary tool for controlling and troubleshooting router hardware, the Junos OS, 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 ports on the front panel.

For information about using the CLI to troubleshoot the Junos OS, see the appropriate Junos OS configuration guide.

Chassis and Interface Alarm Messages

When the Routing Engine detects an alarm condition, it lights the red or yellow alarm LED on the front panel as appropriate. To view a more detailed description of the alarm cause, issue the show chassis alarms command:

There are two classes of alarm messages:

• Chassis alarms—Indicate a problem with a chassis component such as the cooling system or power supplies.
• Interface alarms—Indicate a problem with a specific network interface.

Front Panel LEDs

The front panel on the router contains LEDs and buttons that allow you to troubleshoot the router.

LEDs on the front panel include the following:

• Alarm LEDs—Two LEDs located on the left side of the front panel indicate critical and warning alarms on the MX80 router. The circular LED lights red to indicate a critical condition that can result in a system shutdown. The triangular LED lights yellow to indicate a less severe condition that requires monitoring or maintenance.
• System LED—One LED on the left side of the front panel indicates the status of the MX80 router. The LED is located below the SYS OK label. The LED lights steadily green when the router is functioning normally and blinks green when the router is transitioning online.
• Routing Engine LED—One bi-color LED on the left side of the front panel indicates the status of the Routing Engine. The LED is located below the RE label. The LED is lit steadily green when the Routing Engine is functioning normally and is lit red when the Routing Engine has failed.
• Link LEDs—Four LEDs labeled LINK, indicate the status of the ports for the fixed 10-Gigabit Ethernet MIC. The LED is green when the link is active, and is off when there is no link. The LINK LEDs are located to the right of the port on the front panel.

Component LEDs

The following LEDs are located on various router components and display the status of those components:

• MIC LEDs—One LED labeled OK/FAIL on each MIC faceplate indicates the MIC’s status. For more information, see the MX Series 3D Universal Edge Routers Line Card Guide. On the fixed MX80 router, each RJ-45 port has an additional link LED. The LED is green when the link is active and is off when there is no link.
• Power supply LEDs—One bi-color LED on each power supply faceplate indicate the status of that power supply. The LED is lit green when the power supply is functioning normally and is lit red when the power supply has failed.