Getting Started

An icon at the top left of the web UI’s navigation bar indicates whether notifications are enabled:

notifications off

Horizon installs with notifications globally disabled by default.

Enabling Notifications

  1. Log in to the web UI as a user with administrator privileges.

  2. Click the gear icon in the top right, and under Event Management click On beside Notification Status, and click Update.

notifications-on

The green bell icon indicates that notifications are globally enabled.

The web workflow above is functionally equivalent to editing the notifd-configuration.xml file and setting status="on" in the top-level notifd-configuration element. This configuration file change happens immediately with no need to restart or send an event.

Configuring Destination Paths

A destination path specifies the "who" (recipient), "when" (interval), and "how" (method) of the notification. It also specifies targets for escalation.

Configuring destination paths separately from individual events lets you use the same information for multiple notifications, minimizing duplication and encouraging reuse.

  1. Log in to the web UI as a user with administrator privileges.

  2. Click the gear icon in the top right, and under Event Management choose Configure Notifications>Configure Destination Paths.

  3. Click New Path, fill in the desired information and click Finish.

    1. To edit a destination path, select it from the list in the Destinations Path screen, and click Edit.

Destination paths configuration is stored in the destinationPaths.xml file. Changes to this file happen immediately with no need to restart or send an event.

Configuring Event Notifications

An event notification ties any OpenNMS event with a destination path.

  1. Log in to the web UI as a user with administrator privileges.

  2. Click the gear icon in the top right, and under Event Management choose Configure Notifications>Configure Event Notifications.

    The screen displays a list of events configured for notifications.

  3. Click Add New Event Notification.

  4. Choose an event on which you want to receive a notification and click Next.

  5. Optionally build a rule to match a subset of IP addresses or services and click Validate rule results, then Next (or Skip results validation).

  6. In the Choose Path screen, specify information to include in the notification, including destination path, subject (for an email message), text, etc.

  7. Click Finish.

NOTES: The event notification configuration is stored in the notifications.xml file. Changes to this file are picked up on the fly with no need to restart or send an event.

The filter rule configured in notifications.xml, e.g., <rule>IPADDR != '0.0.0.0'</rule> is not strict by default. That means if there is any event that is not associated with any node/interface, it would not validate rule and by default notification would be saved. A strict rule e.g., <rule strict="true">IPADDR != '0.0.0.0'</rule> will always be evaluated and if there is no node/interface associated with event, the notification would not be saved.

By default, OpenNMS executes the destination path of all notifications matching the event’s UEI. You can configure OpenNMS to execute only the destination path of the first matching notification by editing the notifd-configuration.xml file and setting match-all="false" in the top-level notifd-configuration element. This configuration file change happens immediately with no need to restart or send an event.

Configuring Path Outages

Configuring a path outage lets you suppress notifications for nodes that appear to be down due to a failure in the network path between the nodes and OpenNMS. For example, if a WAN link fails, all nodes at the remote site served by the WAN link will appear to be down. Since we will get a notification that the router on the far end of the WAN link is not responding, we don’t need notifications for all the devices that sit behind that router.

You can configure a path outage for an individual node or create a rule-based configuration for a group of nodes:

  1. Log in to the web UI as a user with administrator privileges.

  2. Click the gear icon in the top right, and under Event Management choose Configure Notifications>Configure Path Outages.

  3. Type the critical path IP address, select a critical path service, and click Next.