Dell Solutions Enabler 10.1.0 Installation and Configuration Guide

Certain events are associated with a numeric value. This value is compared with a set of threshold values, which determine whether the event is delivered and, if so, with what severity. These events are known as threshold events. Each threshold event has a set of default threshold filters defined for it.

For example, the SYMAPI_AEVENT2_UID_THRESH_POOL_FREESPACE event tracks as a percentage (0% - 100%) the space utilization within DSE, Snap and thin pools and has the following default threshold filters defined:

• If value is 100%, deliver event with FATAL severity
• If value is >= 80%, deliver event with CRITICAL severity
• If value is >= 70%, deliver event with MAJOR severity
• If value is >= 65%, deliver event with MINOR severity
• If value is >= 60%, deliver event with WARNING severity

When registering for events, you can specify a custom filter to replace the default one for that event. Each filter contains a set of rules composed of:

• A comparison function: either >= or <=.
• A number (integer) to compare the event value against.
• A severity to deliver the event with - if the comparison succeeds.

These threshold filters define bands of event value. Events are generated as the value crosses from one band to another. For the thresholds in the earlier example, a pool's utilization that rose gradually from 60% to 92% and then dropped back to 50% again would result in delivery of the following events:

WARNING — severity when the value passes 60%

MINOR — severity when the value passes 65%

MAJOR — severity when the value passes 70%

CRITICAL — severity when the value passes 80%

MAJOR — severity when the value drops below 80%

MINOR — severity when the value drops below 70%

WARNING — severity when the value drops below 65%

NORMAL — severity when the value drops below 60%

If an event's value crosses into a range that does not match any of the configured thresholds, the event daemon will automatically deliver an event with a severity of NORMAL to indicate that it no longer falls into one of the defined threshold bands. In essence, NORMAL should serve as an "all-OK" indicator.

There is never a reason to explicitly specify a threshold for the NORMAL severity. It should cover everything that is not explicitly matched.

If the supplied threshold list has only a single filter that performs a comparison against zero, the event daemon will deliver an event every time the event value changes. For example, specifying the following filter:

"If value >= 0 : WARNING"

will deliver an event with WARNING severity every time the value changes.