HP Web Jetadmin - Using Proactive Alerts with HP Web Jetadmin

Eventing

Alerts/events from newer devices are processed using Web Services (WS) Eventing. Unlike traps that

send UDP packets for every single event that occurs on the device, subscriptions to WS events on the

device occur per event, minimizing network traffic. Event payloads from the device have all the

necessary info for the event in the form of an XML document over HTTPS. There is no need to go back

and poll the device, again saving network traffic. Subscriptions will never expire on the device.

Heartbeat events are periodically sent from the device to HP Web Jetadmin during periods of event

inactivity to inform HP Web Jetadmin the subscriptions are still active. Events from the device have a

retry mechanism in case HP Web Jetadmin is down to provide guaranteed delivery.

ALERT SUBSCRIPTION TYPES

HP Web Jetadmin divides alerts into three

subscription types: General, Supplies, and

Critical (see Figure 1). The Supplies type

contains only alerts related to consumables that

are replenished. The General and Critical alerts

types contain a much wider variety of alerts,

including some supplies-related events. Reasons

for subscribing to alerts in one category versus

another are described below.

General Subscription Type

The General alerts type includes a wide variety

of alert categories from service errors to

supplies alerts. Most non-supply device events

rely on traps. Polling is established when trap

destinations can’t be configured, the event

requires a status query because it doesn’t

generate a trap, or a supply level must be

gathered to determine whether the event has occurred.

Advisory

The Advisory category contains events that are warnings

of existing conditions that do not affect the ability of the

device to print jobs. Many of the events are triggered

real time by eventing or traps. The Page Count event will

send an alert when a user-defined page count threshold

is crossed. Web Jetadmin will poll the engine cycle count

object and send the alert when the threshold is crossed.

Media Path

The Media Path category contains events relating to the

path the paper takes through the device. All are

triggered by traps or eventing when available on the

device.

Figure 1—Alert categories