Alarm

Introduction

Alarms can be used in order to specify specific actions to take when a particular event occurs in the system.

Overview

The alarm handling functionality in the system makes use of the following terminology:

Alarm Triggers <----------------------> Alarm Actions
      ^                                       ^
      |                                       |
      |                                       |
      v                                       v
Alarm Sources                           Alarm Targets

Figure 1: The image describes the relations between the different aspects that together constitute the alarm handling functionality in the system. Alarm triggers monitor the state of the provided source and defines conditions that should invoke an associated alarm action. The invoked alarm action specifies what alarm target(s) to use in order to notify the operator.

  • Alarm Sources: An alarm source is an object being monitored by an alarm trigger. This could be, for instance, the link status (up/down) of an ethernet port or the temperature value of a temperature sensor. Alarm sources are described further in a section below.

  • Alarm Triggers: An alarm trigger will monitor a provided alarm source and define the conditions for when specific alarm events occur, in other words, when the trigger becomes active (alarm situation) or inactive (normal operation).

  • Alarm Actions and Alarm Targets: When an alarm event occurs, the operator can be informed in a number of ways. This is defined by a specific alarm action that is associated with any give alarm trigger. The alarm action in turn specify one or more alarm targets that will be used to notify the operator. As an example this could be snmp traps, logging, or a front panel status led. Alarm actions and targets are described in more detail below.

Alarm Triggers and Alarm Sources

The alarm trigger defines rules for when a monitored source should generate an alarm event. The alarm trigger also needs to specify an alarm action to invoke when an alarm event occurs.

The system supports the following alarm sources to be associated with any given alarm trigger:

  • Link Alarm: It is possible to configure link alarm triggers to react when the status of a link changes (goes up or down).

  • Temperature: Temperature alarm triggers can be configured to react when the temperature rises above (or falls below) some defined threshold.

  • Power: A power trigger can monitor one or more power feed sensors. Most WeOS products have two power feeds (single power supply), with a sensor for each power feed. Typically a single power trigger is used to monitor both power feed sensors.

  • Digital-In: Alarms can be triggered depending on the presence of input voltage/current on the Digital-In pins of the Digital I/O connector.

  • Timer: Timer triggers are configured to go off at given time interval.

  • Ping: A connectivity checker, sends an ICMP ping in a configurable interval.

  • FRNT: The FRNT ring status trigger will react when an FRNT ring is broken or healed (intact).

    NOTE: Only an FRNT focal point can determine the ring status with certainty.

  • HW-Failure: Hardware alarms triggers notifies that the unit has detected a hardware failure (typically if an unsupported SFP is inserted).

  • DDM: Digital Diagnostics Monitoring, used to troubleshoot fiber optic connectivity issues. A number of different alarm sources related to DDM exist:

    • ddm-temperature

    • ddm-voltage

    • ddm-bias-current

    • ddm-rx-power

    • ddm-tx-power

  • Rico-uplink: A RICO uplink checker.

  • RING: The RING status trigger will react when an ring is open or closed (intact).

Alarm Actions and Alarm Targets

All alarm actions in the system needs to be associated with one or more alarm targets, these dictate how the activated alarm will be presented to the operator:

  • Led: here are front panel LEDs which can indicate status of specific ports or protocols. There is also a general status LED, which shows a green light when the unit is operating ‘OK’, but shows a red light as soon as any of the associated alarm triggers becomes active. Thus, the ’ON’ LED provides a summary alarm function.

  • Log: Log status change to syslog.

  • SNMP: Alarms can be configured to generate SNMP traps.

  • Digout: On units equipped with a Digital I/O contact, the status relay pins (Digital-Out) can be used as an alarm target. Similar to the ‘ON’ LED, the status relay provides a summary alarm function, where the ‘gate’ is closed when the switch is operating ‘OK’, and open when any of the associated alarm triggers becomes active (or when the unit has no power).

  • Port: Control the admin status of a port.

  • Iface: Control the admin status of an interface.

Configuration

The alarm settings can be found at the top level in the configuration context.

example:/#> configure
example:/config/#> alarm
example:/config/alarm/#>
[no] action [INDEX]

Create, update or remove an alarm action (profile). Use action INDEX to enter the Alarm Action Configuration context and create a new or update an existing action.

Note: Will enter a sub-context. Information on this context can be found in a section below.

no
Remove the specified action.
INDEX
Numerical index value of the action to access, create, or remove.
[no] trigger [INDEX] [TYPE]

Create, update or remove an alarm trigger configuration.

Note: Will enter a sub-context. Information on this context can be found in a section below.

no
Remove the specified trigger.
INDEX
Numerical index value of the trigger to access, create, or remove.
TYPE
Type of trigger to create. Specified in the sections above. The available trigger types can also be seen with the command show types.
[no] types

Show available trigger types.

no
Not applicable for this command.

Trigger Configuration

Trigger configuration is accessed from the top level of the alarm context:

example:/config/alarm/#> trigger TYPE
example:/config/alarm/trigger-1/#>

Where TYPE is the type of trigger that should be created. The types are described above when talking about Alarm Sources. The available types can also be seen with the types command in the cli:

example:/config/alarm/#> types
link-alarm
temperature
power
digin
snr-margin
lff
timer
ping
frnt
sfp-warning
hw-failure
summary-alarm
poe
microlok
ddm-temperature
ddm-voltage
ddm-bias-current
ddm-rx-power
ddm-tx-power
rico-uplink
ring

Note: Depending on the type of trigger selected, additional configuration options may appear in the Trigger configuration context.

[no] enable

Enable or disable the trigger.

no
Disable the trigger.
[no] action [INDEX]

Specify the action (profile) to be invoked when this trigger detects an alarm event.

Default: Index 1 (default action).

no
Disable the mapping to an alarm action.
INDEX
Index of a specific action to associate with the trigger.
[no] condition [high|low]

Define whether the high or low trigger state should be considered the alarm state, while the other is considered the normal state.

Note: Some triggers, such as link-alarm and power triggers have a static (predefined) alarm condition setting. (Both link-alarm and power triggers have condition set to low). For other triggers, the alarm condition setting is configurable.

Default: Differs between different trigger types.

no
Reset option to default.
[no] severity [LEVEL] | [active <LEVEL>] [inactive <LEVEL>]

Specify the severity level of active and inactive alarm events detected by this trigger.

Active and inactive severity levels can be configured together or independently.

Default: active to warning and inactive to notice.

no
Set severity to level none. Alarm events with severity none will not cause SNMP traps to be sent or events to be logged, however, such events can still affect the status relay (digital-out) and ON LED targets.
LEVEL

The levels uses standard syslog levels:

none : No severity.

debug : System is unusable.

info : Informational message.

noitce : Normal, but significant, condition.

warning : Normal, but significant, condition.

err : Error conditions.

crit : Critical conditions.

alert : Action must be taken immediately.

emerg : System is unusable

Action Configuration

Action configuration is accessed from the top level of the alarm context. If no specific index is provided, a new action with an unused index will be created. In order to access a existing action the index must be provided.

example:/config/alarm/#> action
example:/config/alarm/action-2/#>
[no] target [TYPE]

Add or remove alarm target to an alarm action (profile).

Note: Depending on the selected target type, additional configuration options that need to be set can appear. For instance, if the target type port is selected, specific port interfaces needs to be specified.

no
Remove any configured targets.
TYPE

led : ON/Status LED.

log : Log status change to syslog.

snmp : Generate an SNMP trap.

digout : Control the status relay.

port : Control the admin status of a port.

iface : Control the admin status of an interface.

Status

In order to see all the currently configured alarms on the system, the following command can be invoked from the top level in the CLI:

example:/#> show alarm
NO TRIGGER          ENA ACT REASON                                            
 1 temperature      YES  NO

If one of the alarms have been triggered, the same command will also display that the alarm is active along with the reason why:

example:/#> show alarm
NO TRIGGER          ENA ACT REASON                                            
 1 temperature      YES YES Temperature is 40.75 degrees Celsius