Chassis And Interface Alarm Messages; Alarm Relay Contacts - Juniper MX2020 Hardware Manual

Alarm devices connected to the alarm relay contact—When a red or yellow alarm occurs, it trips the
corresponding alarm relay.
CLI—The CLI is the primary tool for controlling and troubleshooting hardware, Junos OS, routing protocols,
and network connectivity. CLI commands display information about 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 Routing
Engine.
For information about using the CLI to troubleshoot the 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 here, contact JTAC.

Chassis and Interface Alarm Messages

When the Control Board and Routing Engine (CB-RE) detects an alarm condition, it lights the red or yellow
alarm LED on the craft interface as appropriate, trips the alarm relay, and reports the cause of the alarm
in the craft interface. 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 system.
Interface alarms indicate a problem with a specific network interface.
user@host> show chassis alarms
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.

Alarm Relay Contacts

The craft interface has two alarm relay contacts for connecting the router to external alarm devices.
Whenever a system condition triggers either the red or yellow alarm on the craft interface, the alarm relay
contacts are also activated. The alarm relay contacts are located on the upper right of the craft interface.
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