Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

Interface Alarms

 
Summary

This section describes interface alarms and how to configure them.

Alarm Overview

Alarms alert you to conditions on a network interface, on the device chassis, or in the system software that might prevent the device from operating normally. You can set the conditions that trigger alarms on an interface. Chassis and system alarm conditions are preset.

An active alarm lights the ALARM LED on the front panel of the device. You can monitor active alarms from the J-Web user interface or the CLI. When an alarm condition triggers an alarm, the device lights the yellow (amber) ALARM LED on the front panel. When the condition is corrected, the light turns off.

Alarm Types

The device supports three types of alarms:

  • Interface alarms indicate a problem in the state of the physical links on fixed or installed Physical Interface Modules (PIMs). To enable interface alarms, you must configure them.

  • Chassis alarms indicate a failure on the device or one of its components. Chassis alarms are preset and cannot be modified.

  • System alarms indicate a missing rescue configuration or software license, where valid. System alarms are preset and cannot be modified, although you can configure them to appear automatically in the J-Web user interface or CLI.

Starting with Junos OS Release 15.1X49-D60 and Junos OS Release 17.3R1, a new system alarm is introduced to indicate that the PICs (I/O card or SPC) have failed to come online during system start time.

Starting in Junos OS Releases 12.3X48-D85, 15.1X49-D180, and 19.2R1, a system alarm is triggered when the Network Security Process (NSD) is unable to restart due to the failure of one or more NSD subcomponents. The alarm logs about the NSD are saved in the messages log. The alarm is automatically cleared when NSD restarts successfully. The show chassis alarms and show system alarms commands are updated to display the following output when NSD is unable to restart - NSD fails to restart because subcomponents fail.

Note

Run the following commands when the CLI prompt indicates that an alarm has been raised:

  • show system alarms

  • show chassis alarms

  • show chassis fpc pic-status

For more information about the CLI commands, see show system alarms, show chassis alarms, and show chassis fpc.

Alarm Severity

Alarms have two severity levels:

  • Major (red)—Indicates a critical situation on the device that has resulted from one of the following conditions. A red alarm condition 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 (yellow)—Indicates a noncritical condition on the device that, if left unchecked, might cause an interruption in service or degradation in performance. A yellow alarm condition requires monitoring or maintenance.

    A missing rescue configuration or software license generates a yellow system alarm.

Alarm Conditions

To enable alarms on a device interface, you must select an alarm condition and an alarm severity. In contrast, alarm conditions and severity are preconfigured for chassis alarms and system alarms.

Note

For information about chassis alarms for your device, see the Hardware Guide for your device.

This section contains the following topics:

Interface Alarm Conditions

Table 1 lists the interface conditions, sorted by interface type, that you can configure for an alarm. You can configure each alarm condition to trigger either a major (red) alarm or minor a (yellow) alarm. The corresponding configuration option is included.

For the services stateful firewall filters (NAT, IDP, and IPsec), which operate on an internal adaptive services module within a device, you can configure alarm conditions on the integrated services and services interfaces.

Table 1: Interface Alarm Conditions

Interface

Alarm Condition

Description

Configuration Option

DS1 (T1)

Alarm indication signal (AIS)

The normal T1 traffic signal contained a defect condition and has been replaced by the AIS. A transmission interruption occurred at the remote endpoint or upstream of the remote endpoint. This all-ones signal is transmitted to prevent consequential downstream failures or alarms.

ais

Yellow alarm

The remote endpoint is in yellow alarm failure. This condition is also known as a far-end alarm failure.

ylw

Ethernet

Link is down

The physical link is unavailable.

link-down

Integrated services

Hardware or software failure

On the adaptive services module, either the hardware associated with the module or the software that drives the module has failed.

failure

Serial

Clear-to-send (CTS) signal absent

The remote endpoint of the serial link is not transmitting a CTS signal. The CTS signal must be present before data can be transmitted across a serial link.

cts-absent

Data carrier detect (DCD) signal absent

The remote endpoint of the serial link is not transmitting a DCD signal. Because the DCD signal transmits the state of the device, no signal probably indicates that the remote endpoint of the serial link is unavailable.

dcd-absent

Data set ready (DSR) signal absent

The remote endpoint of the serial link is not transmitting a DSR signal. The DSR signal indicates that the remote endpoint is ready to receive and transmit data across the serial link.

dsr-absent

Loss of receive clock

The clock signal from the remote endpoint is not present. Serial connections require clock signals to be transmitted from one endpoint and received by the other endpoint of the link.

loss-of-rx-clock

Loss of transmit clock

The local clock signal is not present. Serial connections require clock signals to be transmitted from one endpoint and received by the other endpoint of the link.

loss-of-tx-clock

Services

Services module hardware down

A hardware problem has occurred on the device's services module. This error typically means that one or more of the CPUs on the module has failed.

hw-down

Services link down

The link between the device and its services module is unavailable.

linkdown

Services module held in reset

The device's services module is stuck in reset mode. If the services module fails to start up five or more times in a row, the services module is held in reset mode. Startup fails when the amount of time from CPU release to CPU halt is less than 300 seconds.

pic-hold-reset

Services module reset

The device's services module is resetting. The module resets after it crashes or is reset from the CLI, or when it takes longer than 60 seconds to start up.

pic-reset

Services module software down

A software problem has occurred on the device's services module.

sw-down

E3

Alarm indication signal (AIS)

The normal E3 traffic signal contained a defect condition and has been replaced by the AIS. A transmission interruption occurred at the remote endpoint or upstream of the remote endpoint. This all-ones signal is transmitted to prevent consequential downstream failures or alarms.

ais

Loss of signal (LOS)

No remote E3 signal is being received at the E3 interface.

los

Out of frame (OOF)

An OOF condition has existed for 10 seconds. This alarm applies only to E3 interfaces configured in frame mode. The OOF failure is cleared when no OOF or LOS defects have occurred for 20 seconds.

oof

Remote defect indication

An AIS, LOS, or OOF condition exists. This alarm applies only to E3 interfaces configured in frame mode.

rdi

T3 (DS3)

Alarm indication signal

The normal T3 traffic signal contained a defect condition and has been replaced by the AIS. A transmission interruption occurred at the remote endpoint or upstream of the remote endpoint. This all-ones signal is transmitted to prevent consequential downstream failures or alarms.

ais

Excessive number of zeros

The bit stream received from the upstream host has more consecutive zeros than are allowed in a T3 frame.

exz

Far-end receive failure (FERF)

The remote endpoint of the connection has failed. A FERF differs from a yellow alarm, because the failure can be any failure, not just an OOF or LOS failure.

ferf

Idle alarm

The Idle signal is being received from the remote endpoint.

idle

Line code violation

Either the line encoding along the T3 link is corrupted or a mismatch between the encoding at the local and remote endpoints of a T3 connection occurred.

lcv

Loss of frame (LOF)

An OOF or loss-of-signal LOS condition has existed for 10 seconds. The LOF failure is cleared when no OOF or LOS defects have occurred for 20 seconds. A LOF failure is also called a red failure.

lof

Loss of signal (LOS)

No remote T3 signal is being received at the T3 interface.

los

Phase-locked loop out of lock

The clocking signals for the local and remote endpoints no longer operate in lock-step.

pll

Yellow alarm

The remote endpoint is in yellow alarm failure. This condition is also known as a far-end alarm failure.

ylw

System Alarm Conditions

Table 2 lists the two preset system alarms, the condition that triggers each alarm, and the action you take to correct the condition.

Table 2: System Alarm Conditions and Corrective Actions

Alarm Type

Alarm Condition

Corrective Action

Configuration

The rescue configuration is not set.

Set the rescue configuration.

License

You have configured at least one software feature that requires a feature license, but no valid license for the feature is currently installed.

Note: This alarm indicates that you are in violation of the software license agreement. You must install a valid license key to be in compliance with all agreements.

Install a valid license key.

Example: Configuring Interface Alarms

This example shows how to configure interface alarms.

Requirements

Before you begin:

  • Establish basic connectivity.

  • Configure network interfaces. See Interfaces User Guide for Security Devices.

  • Select the network interface on which to apply an alarm and the condition you want to trigger the alarm.

Overview

In this example, you enable interface alarms by explicitly setting alarm conditions. You configure the system to generate a red interface alarm when a yellow alarm is detected on a DS1 link. You configure the system to generate a red interface alarm when a link-down failure is detected on an Ethernet link.

For a serial link, you set cts-absent and dcd-absent to yellow to signify either the CST or the DCD signal is not detected. You set loss-of-rx-clock and loss-of-tx-clock to red alarm to signify either the receiver clock signal or the transmission clock signal is not detected.

For a T3 link, you set the interface alarm to red when the remote endpoint is experiencing a failure. You set exz to yellow alarm when the upstream bit has more consecutive zeros than are permitted in a T3 interface. You then set a red alarm when there is loss-of-signal on the interface.

Finally, you configure the system to display active system alarms whenever a user with the login class admin logs in to the device.

Configuration

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, copy and paste the commands into the CLI at the [edit] hierarchy level, and then enter commit from configuration mode.

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For instructions on how to do that, see Using the CLI Editor in Configuration Mode in the Junos OS CLI User Guide .

To configure interface alarms:

  1. Configure an alarm.
  2. Specify the interface alarms on a DS1 and an Ethernet link.
  3. Specify the interface alarms on a serial link.
  4. Specify the interface alarms on a T3 link.
  5. Configure the system to display active system alarms.

Results

From configuration mode, confirm your configuration by entering the show chassis alarms and show system login commands. If the output does not display the intended configuration, repeat the configuration instructions in this example to correct it.

If you are done configuring the device, enter commit from configuration mode.

Verification

Verifying the Alarm Configurations

Purpose

Confirm that the configuration is working properly.

Verify that the alarms are configured.

Action

From configuration mode, enter the show chassis alarms command. Verify that the output shows the intended configuration of the alarms.

Release History Table
Release
Description
Starting with Junos OS Release 15.1X49-D60 and Junos OS Release 17.3R1, a new system alarm is introduced to indicate that the PICs (I/O card or SPC) have failed to come online during system start time.
Starting in Junos OS Releases 12.3X48-D85, 15.1X49-D180, and 19.2R1, a system alarm is triggered when the Network Security Process (NSD) is unable to restart due to the failure of one or more NSD subcomponents. The alarm logs about the NSD are saved in the messages log. The alarm is automatically cleared when NSD restarts successfully. The show chassis alarms and show system alarms commands are updated to display the following output when NSD is unable to restart - NSD fails to restart because subcomponents fail.