Troubleshoot the MX301

This topic contains some common troubleshooting resources for the MX301 and a list of alarms and how to fix them.

Troubleshooting Resources for MX301

Use the messages on the status panel on the front panel and LEDs on the components to identify alarm conditions and the Junos OS CLI to troubleshoot the device. You can also contact the Juniper Networks® Technical Assistance Center (JTAC) for support.

Status panel—When the device detects an alarm condition, it is displayed on the status panel.
LEDs—When the device detects an alarm condition, the alarm LED on an interface glows red or yellow.
CLI—The CLI is the primary tool for controlling and troubleshooting hardware, Junos OS, and network connectivity. CLI command outputs display information about network connectivity, which Junos derives from the ping and traceroute utilities. You can use the CLI to see more information about alarm conditions.

For information about using the CLI to troubleshoot Junos OS, see the appropriate Junos OS configuration guide.
JTAC—If you need assistance during troubleshooting, you can contact the Juniper Networks Technical Assistance Center (JTAC) by using the Web or by telephone. If you encounter software problems, or problems with hardware components not discussed in this guide, contact JTAC.

Table 1: Alarm Terms
Term	Definition
Alarm	A signal alerting you to conditions that might prevent normal operation. On a device, the alarm signal is the red system LED that is lit on the front of the chassis.
Alarm condition	A failure event that triggers an alarm.
Alarm severity	The seriousness of the alarm. The level of severity can be either major or minor.

Alarm Types

Table 2: Alarm Types
Term	Definition
Chassis alarms	A predefined alarm triggered by a physical condition in the device such as a power supply failure or excessive component temperature.
Interface alarms	An alarm that you configure to alert you when an interface link is down. This applies to Ethernet, Fibre Channel, and management Ethernet interfaces. You can set the alarm as major or minor for a specific link-down condition or have the condition ignored.
System alarms	A predefined alarm that might be triggered by a missing rescue configuration, failure to install a license for a licensed software feature, or high disk usage. You can configure system alarms to appear automatically in the J-Web interface display or CLI display.

Alarm Severity

Table 3: Alarm Severity
Term	Definition
Major (red)	Indicates a critical situation on the router that has resulted from one of the following conditions and that requires immediate action: One or more hardware components have failed. One or more hardware components have exceeded temperature thresholds. An alarm condition configured on an interface has triggered a critical warning.
Minor (amber or blinking red)	Indicates a noncritical condition in the router that, if left unchecked, might cause an interruption in service or degradation in performance. A minor alarm condition requires monitoring or maintenance. For example, a missing rescue configuration generates a minor system alarm.

Use the RESET Button

If a configuration fails or you lose management access to the router because of a configuration change, you can use the RESET button to restore the device.

The RESET button on the MX301 is recessed to prevent it from being pressed accidentally. To press the RESET button, insert a small probe (such as a straightened paper clip) into the pinhole above the RESET label on the front panel.

Press the RESET button momentarily to reboot the device.
Press and hold the RESET button for approximately 10 seconds to reboot the device and enter the BIOS reset mode.